Hi!
It lasted longer (2685 minutes, almost 45 hours), but then disconnected again. The logs (with more context this time):
Sun Apr 26 02:06:34 2020 daemon.notice hostapd: wlan0: AP-STA-DISCONNECTED 10:XX:XX:XX:XX:aa
Sun Apr 26 02:06:34 2020 daemon.info hostapd: wlan0: STA 10:XX:XX:XX:XX:aa IEEE 802.11: disassociated due to inactivity
Sun Apr 26 02:06:35 2020 daemon.info hostapd: wlan0: STA 10:XX:XX:XX:XX:aa IEEE 802.11: deauthenticated due to inactivity (timer DEAUTH/REMOVE)
Sun Apr 26 02:08:23 2020 daemon.info dnsmasq-dhcp[1565]: DHCPREQUEST(br-lan) 192.168.1.197 14:XX:XX:XX:XX:43
Sun Apr 26 02:08:23 2020 daemon.info dnsmasq-dhcp[1565]: DHCPACK(br-lan) 192.168.1.197 14:XX:XX:XX:XX:43 XXXXX-tablet
Sun Apr 26 04:48:39 2020 daemon.info dnsmasq-dhcp[1565]: DHCPREQUEST(br-lan) 192.168.1.193 58:XX:XX:XX:XX:b9
Sun Apr 26 04:48:39 2020 daemon.info dnsmasq-dhcp[1565]: DHCPACK(br-lan) 192.168.1.193 58:XX:XX:XX:XX:b9 StarJupiter
Sun Apr 26 05:24:22 2020 daemon.info dnsmasq[1565]: read /etc/hosts - 4 addresses
Sun Apr 26 05:24:22 2020 daemon.info dnsmasq[1565]: read /tmp/hosts/odhcpd - 1 addresses
Sun Apr 26 05:24:22 2020 daemon.info dnsmasq[1565]: read /tmp/hosts/dhcp.cfg01411c - 2 addresses
Sun Apr 26 05:24:22 2020 daemon.info dnsmasq-dhcp[1565]: read /etc/ethers - 0 addresses
Sun Apr 26 06:28:56 2020 daemon.info dnsmasq-dhcp[1565]: DHCPREQUEST(br-lan) 192.168.1.111 b4:XX:XX:XX:XX:63
Sun Apr 26 06:28:56 2020 daemon.info dnsmasq-dhcp[1565]: DHCPACK(br-lan) 192.168.1.111 b4:XX:XX:XX:XX:63 HUAWEI_XXXXXXXXb6
Sun Apr 26 06:49:46 2020 daemon.info dnsmasq-dhcp[1565]: DHCPREQUEST(br-lan) 192.168.1.225 80:XX:XX:XX:XX:ac
Sun Apr 26 06:49:46 2020 daemon.info dnsmasq-dhcp[1565]: DHCPACK(br-lan) 192.168.1.225 80:XX:XX:XX:XX:ac NPXXXXXXAC
Sun Apr 26 07:27:47 2020 daemon.notice pppd[13073]: Modem hangup
Sun Apr 26 07:27:47 2020 daemon.info pppd[13073]: Connect time 2685.2 minutes.
Sun Apr 26 07:27:47 2020 daemon.info pppd[13073]: Sent 729073864 bytes, received 3334049944 bytes.
Sun Apr 26 07:27:47 2020 daemon.notice netifd: Network device 'pppoe-wan' link is down
Sun Apr 26 07:27:47 2020 daemon.debug pppd[13073]: Script /lib/netifd/ppp-down started (pid 12229)
Sun Apr 26 07:27:47 2020 daemon.notice pppd[13073]: Connection terminated.
Sun Apr 26 07:27:47 2020 daemon.debug pppd[13073]: Send PPPOE Discovery V1T1 PADT session 0x1 length 28
Sun Apr 26 07:27:47 2020 daemon.debug pppd[13073]: dst a4:XX:XX:XX:XX:44 src c4:XX:XX:XX:XX:ed
Sun Apr 26 07:27:47 2020 daemon.debug pppd[13073]: [host-uniq 00 00 33 11] [AC-cookie ed XY XY XY XY XY XY XY XY XY XY XY XY XY XY 75]
Sun Apr 26 07:27:47 2020 daemon.info pppd[13073]: Sent PADT
Sun Apr 26 07:27:47 2020 daemon.debug pppd[13073]: Waiting for 1 child processes...
Sun Apr 26 07:27:47 2020 daemon.debug pppd[13073]: script /lib/netifd/ppp-down, pid 12229
Sun Apr 26 07:27:47 2020 daemon.notice netifd: Interface 'wan' has lost the connection
Sun Apr 26 07:27:47 2020 daemon.warn dnsmasq[1565]: no servers found in /tmp/resolv.conf.auto, will retry
Sun Apr 26 07:27:47 2020 daemon.debug pppd[13073]: Script /lib/netifd/ppp-down finished (pid 12229), status = 0x1
Sun Apr 26 07:27:47 2020 daemon.info pppd[13073]: Exit.
Sun Apr 26 07:27:47 2020 daemon.notice netifd: Interface 'wan' is now down
Sun Apr 26 07:27:47 2020 kern.info kernel: [568664.315207] device eth1 left promiscuous mode
Sun Apr 26 07:27:47 2020 kern.info kernel: [568664.336744] device eth1.3902 left promiscuous mode
Sun Apr 26 07:27:47 2020 kern.info kernel: [568664.357548] eth1: link down
Sun Apr 26 07:27:47 2020 daemon.notice netifd: Interface 'wan' is disabled
Sun Apr 26 07:27:47 2020 kern.info kernel: [568664.382817] IPv6: ADDRCONF(NETDEV_UP): eth1: link is not ready
Sun Apr 26 07:27:47 2020 kern.info kernel: [568664.390113] eth1: link up (1000Mbps/Full duplex)
Sun Apr 26 07:27:47 2020 kern.info kernel: [568664.434812] IPv6: ADDRCONF(NETDEV_CHANGE): eth1: link becomes ready
Sun Apr 26 07:27:47 2020 daemon.notice netifd: Interface 'wan' is enabled
Sun Apr 26 07:27:47 2020 daemon.notice netifd: Interface 'wan' is setting up now
Sun Apr 26 07:27:47 2020 daemon.err insmod: module is already loaded - slhc
Sun Apr 26 07:27:47 2020 daemon.err insmod: module is already loaded - ppp_generic
Sun Apr 26 07:27:47 2020 daemon.err insmod: module is already loaded - pppox
Sun Apr 26 07:27:47 2020 daemon.err insmod: module is already loaded - pppoe
Sun Apr 26 07:27:48 2020 daemon.info pppd[12291]: Plugin rp-pppoe.so loaded.
Sun Apr 26 07:27:48 2020 daemon.info pppd[12291]: RP-PPPoE plugin version 3.8p compiled against pppd 2.4.7
Sun Apr 26 07:27:48 2020 daemon.notice pppd[12291]: pppd 2.4.7 started by root, uid 0
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: Send PPPOE Discovery V1T1 PADI session 0x0 length 12
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: dst ff:ff:ff:ff:ff:ff src c4:XX:XX:XX:XX:ed
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: [service-name] [host-uniq 00 00 30 03]
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: Recv PPPOE Discovery V1T1 PADO session 0x0 length 51
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: dst c4:XX:XX:XX:XX:ed src a4:XX:XX:XX:XX:44
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: [service-name] [AC-name SIMB_TABOR_BNG1] [host-uniq 00 00 30 03] [AC-cookie ed XY XY XY XY XY XY XY XY XY XY XY XY XY XY 75]
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: Send PPPOE Discovery V1T1 PADR session 0x0 length 32
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: dst a4:XX:XX:XX:XX:44 src c4:XX:XX:XX:XX:ed
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: [service-name] [host-uniq 00 00 30 03] [AC-cookie ed XY XY XY XY XY XY XY XY XY XY XY XY XY XY 75]
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: Recv PPPOE Discovery V1T1 PADS session 0x1 length 12
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: dst c4:XX:XX:XX:XX:ed src a4:XX:XX:XX:XX:44
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: [service-name] [host-uniq 00 00 30 03]
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: PADS: Service-Name: ''
Sun Apr 26 07:27:48 2020 daemon.info pppd[12291]: PPP session is 1
Sun Apr 26 07:27:48 2020 daemon.warn pppd[12291]: Connected to a4:XX:XX:XX:XX:44 via interface eth1.3902
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: using channel 13
Sun Apr 26 07:27:48 2020 kern.info kernel: [568664.916849] pppoe-wan: renamed from ppp0
Sun Apr 26 07:27:48 2020 daemon.info pppd[12291]: Renamed interface ppp0 to pppoe-wan
Sun Apr 26 07:27:48 2020 daemon.info pppd[12291]: Using interface pppoe-wan
Sun Apr 26 07:27:48 2020 daemon.notice pppd[12291]: Connect: pppoe-wan <--> eth1.3902
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: sent [LCP ConfReq id=0x1 <mru 1492> <magic 0x899f5a8a>]
Sun Apr 26 07:27:48 2020 daemon.debug pppd[12291]: rcvd [LCP ConfAck id=0x1 <mru 1492> <magic 0x899f5a8a>]
Sun Apr 26 07:27:51 2020 daemon.debug pppd[12291]: sent [LCP ConfReq id=0x1 <mru 1492> <magic 0x899f5a8a>]
Sun Apr 26 07:27:51 2020 daemon.debug pppd[12291]: rcvd [LCP ConfAck id=0x1 <mru 1492> <magic 0x899f5a8a>]
Sun Apr 26 07:27:51 2020 daemon.debug pppd[12291]: rcvd [LCP ConfReq id=0x5 <mru 1492> <auth chap MD5> <magic 0x51d7b53f>]
Sun Apr 26 07:27:51 2020 daemon.debug pppd[12291]: sent [LCP ConfAck id=0x5 <mru 1492> <auth chap MD5> <magic 0x51d7b53f>]
Sun Apr 26 07:27:51 2020 daemon.debug pppd[12291]: sent [LCP EchoReq id=0x0 magic=0x899f5a8a]
Sun Apr 26 07:27:51 2020 daemon.debug pppd[12291]: rcvd [CHAP Challenge id=0x1 <e8****************************************************************************************************************fd>, name = "SIMB_TABOR_BNG1"]
Sun Apr 26 07:27:51 2020 daemon.debug pppd[12291]: sent [CHAP Response id=0x1 <3a****************************52>, name = "username"]
Sun Apr 26 07:27:51 2020 daemon.debug pppd[12291]: rcvd [LCP EchoRep id=0x0 magic=0x51d7b53f]
Sun Apr 26 07:27:51 2020 daemon.debug pppd[12291]: rcvd [CHAP Success id=0x1 "CHAP authentication success"]
Sun Apr 26 07:27:51 2020 daemon.info pppd[12291]: CHAP authentication succeeded: CHAP authentication success
Sun Apr 26 07:27:51 2020 daemon.notice pppd[12291]: CHAP authentication succeeded
Sun Apr 26 07:27:51 2020 daemon.notice pppd[12291]: peer from calling number A4:XX:XX:XX:XX:44 authorized
Sun Apr 26 07:27:52 2020 daemon.debug pppd[12291]: sent [IPCP ConfReq id=0x1 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns2 0.0.0.0>]
Sun Apr 26 07:27:52 2020 daemon.debug pppd[12291]: sent [IPV6CP ConfReq id=0x1 <addr fe80::****:****:****:618d>]
Sun Apr 26 07:27:52 2020 daemon.debug pppd[12291]: rcvd [IPCP ConfReq id=0xa8 <addr 94.XX.YY.0>]
Sun Apr 26 07:27:52 2020 daemon.debug pppd[12291]: sent [IPCP ConfAck id=0xa8 <addr 94.XX.YY.0>]
Sun Apr 26 07:27:52 2020 daemon.debug pppd[12291]: rcvd [IPCP ConfNak id=0x1 <addr 46.XX.YY.17> <ms-dns1 212.18.32.10> <ms-dns2 212.18.32.12>]
Sun Apr 26 07:27:52 2020 daemon.debug pppd[12291]: sent [IPCP ConfReq id=0x2 <addr 46.XX.YY.17> <ms-dns1 212.18.32.10> <ms-dns2 212.18.32.12>]
Sun Apr 26 07:27:52 2020 daemon.debug pppd[12291]: rcvd [IPCP ConfAck id=0x2 <addr 46.XX.YY.17> <ms-dns1 212.18.32.10> <ms-dns2 212.18.32.12>]
Sun Apr 26 07:27:52 2020 daemon.notice pppd[12291]: local IP address 46.XX.YY.17
Sun Apr 26 07:27:52 2020 daemon.notice pppd[12291]: remote IP address 94.XX.YY.0
Sun Apr 26 07:27:52 2020 daemon.notice pppd[12291]: primary DNS address 212.18.32.10
Sun Apr 26 07:27:52 2020 daemon.notice pppd[12291]: secondary DNS address 212.18.32.12
Sun Apr 26 07:27:52 2020 daemon.debug pppd[12291]: Script /lib/netifd/ppp-up started (pid 12357)
Sun Apr 26 07:27:52 2020 daemon.notice netifd: Network device 'pppoe-wan' link is up
Sun Apr 26 07:27:52 2020 daemon.notice netifd: Interface 'wan' is now up
Sun Apr 26 07:27:52 2020 daemon.info dnsmasq[1565]: reading /tmp/resolv.conf.auto
Sun Apr 26 07:27:52 2020 daemon.info dnsmasq[1565]: using local addresses only for domain test
Sun Apr 26 07:27:52 2020 daemon.info dnsmasq[1565]: using local addresses only for domain onion
Sun Apr 26 07:27:52 2020 daemon.info dnsmasq[1565]: using local addresses only for domain localhost
Sun Apr 26 07:27:52 2020 daemon.info dnsmasq[1565]: using local addresses only for domain local
Sun Apr 26 07:27:52 2020 daemon.info dnsmasq[1565]: using local addresses only for domain invalid
Sun Apr 26 07:27:52 2020 daemon.info dnsmasq[1565]: using local addresses only for domain bind
Sun Apr 26 07:27:52 2020 daemon.debug pppd[12291]: Script /lib/netifd/ppp-up finished (pid 12357), status = 0x1
Sun Apr 26 07:27:52 2020 daemon.info dnsmasq[1565]: using local addresses only for domain lan
Sun Apr 26 07:27:52 2020 daemon.info dnsmasq[1565]: using nameserver 212.18.32.10#53
Sun Apr 26 07:27:52 2020 daemon.info dnsmasq[1565]: using nameserver 212.18.32.12#53
Sun Apr 26 07:27:52 2020 user.notice firewall: Reloading firewall due to ifup of wan (pppoe-wan)
Sun Apr 26 07:27:55 2020 daemon.debug pppd[12291]: sent [IPV6CP ConfReq id=0x1 <addr fe80::2c4c:f4e9:11dd:618d>]
Sun Apr 26 07:27:58 2020 daemon.debug pppd[12291]: sent [IPV6CP ConfReq id=0x1 <addr fe80::2c4c:f4e9:11dd:618d>]
Sun Apr 26 07:28:01 2020 daemon.debug pppd[12291]: sent [IPV6CP ConfReq id=0x1 <addr fe80::2c4c:f4e9:11dd:618d>]
Sun Apr 26 07:28:04 2020 daemon.debug pppd[12291]: sent [IPV6CP ConfReq id=0x1 <addr fe80::2c4c:f4e9:11dd:618d>]
Sun Apr 26 07:28:07 2020 daemon.debug pppd[12291]: sent [IPV6CP ConfReq id=0x1 <addr fe80::2c4c:f4e9:11dd:618d>]
Sun Apr 26 07:28:10 2020 daemon.debug pppd[12291]: sent [IPV6CP ConfReq id=0x1 <addr fe80::2c4c:f4e9:11dd:618d>]
Sun Apr 26 07:28:13 2020 daemon.debug pppd[12291]: sent [IPV6CP ConfReq id=0x1 <addr fe80::2c4c:f4e9:11dd:618d>]
Sun Apr 26 07:28:16 2020 daemon.debug pppd[12291]: sent [IPV6CP ConfReq id=0x1 <addr fe80::2c4c:f4e9:11dd:618d>]
Sun Apr 26 07:28:19 2020 daemon.debug pppd[12291]: sent [IPV6CP ConfReq id=0x1 <addr fe80::2c4c:f4e9:11dd:618d>]
Sun Apr 26 07:28:22 2020 daemon.warn pppd[12291]: IPV6CP: timeout sending Config-Requests
Sun Apr 26 07:39:46 2020 daemon.info dnsmasq-dhcp[1565]: DHCPREQUEST(br-lan) 192.168.1.197 14:XX:XX:XX:XX:43
Sun Apr 26 07:39:46 2020 daemon.info dnsmasq-dhcp[1565]: DHCPACK(br-lan) 192.168.1.197 14:XX:XX:XX:XX:43 XXXXX-tablet