Did you have any success? I am having a similar issue on Eir (formally Eircom) in Ireland.
Wed Jul 12 00:05:50 2017 daemon.notice netifd: Interface 'wan' is setting up now
Wed Jul 12 00:05:50 2017 kern.info kernel: [ 470.999733] mv643xx_eth_port mv643xx_eth_port.1 eth1: link up, 1000 Mb/s, full duplex, flow control disabled
Wed Jul 12 00:05:50 2017 daemon.info pppd[6210]: Plugin rp-pppoe.so loaded.
Wed Jul 12 00:05:50 2017 daemon.info pppd[6210]: RP-PPPoE plugin version 3.8p compiled against pppd 2.4.7
Wed Jul 12 00:05:50 2017 daemon.notice pppd[6210]: pppd 2.4.7 started by root, uid 0
Wed Jul 12 00:05:50 2017 daemon.debug pppd[6210]: Send PPPOE Discovery V1T1 PADI session 0x0 length 4
Wed Jul 12 00:05:50 2017 daemon.debug pppd[6210]: dst ff:ff:ff:ff:ff:ff src 58:6d:8f:f5:cb:7d
Wed Jul 12 00:05:50 2017 daemon.debug pppd[6210]: [service-name]
Wed Jul 12 00:05:55 2017 daemon.debug pppd[6210]: Send PPPOE Discovery V1T1 PADI session 0x0 length 4
Wed Jul 12 00:05:55 2017 daemon.debug pppd[6210]: dst ff:ff:ff:ff:ff:ff src 58:6d:8f:f5:cb:7d
Wed Jul 12 00:05:55 2017 daemon.debug pppd[6210]: [service-name]
Wed Jul 12 00:06:00 2017 daemon.debug pppd[6210]: Send PPPOE Discovery V1T1 PADI session 0x0 length 4
Wed Jul 12 00:06:00 2017 daemon.debug pppd[6210]: dst ff:ff:ff:ff:ff:ff src 58:6d:8f:f5:cb:7d
Wed Jul 12 00:06:00 2017 daemon.debug pppd[6210]: [service-name]
Wed Jul 12 00:06:05 2017 daemon.warn pppd[6210]: Timeout waiting for PADO packets
Wed Jul 12 00:06:05 2017 daemon.err pppd[6210]: Unable to complete PPPoE Discovery
Wed Jul 12 00:06:05 2017 daemon.info pppd[6210]: Exit.
Wed Jul 12 00:06:05 2017 daemon.notice netifd: Interface 'wan' is now down
Wed Jul 12 00:06:05 2017 daemon.notice netifd: Interface 'wan' is disabled
Wed Jul 12 00:06:05 2017 daemon.notice netifd: Interface 'wan' is enabled
Wed Jul 12 00:06:05 2017 daemon.notice netifd: Interface 'wan' is setting up now
Wed Jul 12 00:06:05 2017 kern.info kernel: [ 486.179716] mv643xx_eth_port mv643xx_eth_port.1 eth1: link up, 1000 Mb/s, full duplex, flow control disabled
Wed Jul 12 00:06:05 2017 daemon.info pppd[6325]: Plugin rp-pppoe.so loaded.
Wed Jul 12 00:06:05 2017 daemon.info pppd[6325]: RP-PPPoE plugin version 3.8p compiled against pppd 2.4.7
Wed Jul 12 00:06:05 2017 daemon.notice pppd[6325]: pppd 2.4.7 started by root, uid 0
Wed Jul 12 00:06:05 2017 daemon.debug pppd[6325]: Send PPPOE Discovery V1T1 PADI session 0x0 length 4
Wed Jul 12 00:06:05 2017 daemon.debug pppd[6325]: dst ff:ff:ff:ff:ff:ff src 58:6d:8f:f5:cb:7d
Wed Jul 12 00:06:05 2017 daemon.debug pppd[6325]: [service-name]
Wed Jul 12 00:06:10 2017 daemon.debug pppd[6325]: Send PPPOE Discovery V1T1 PADI session 0x0 length 4
Wed Jul 12 00:06:10 2017 daemon.debug pppd[6325]: dst ff:ff:ff:ff:ff:ff src 58:6d:8f:f5:cb:7d
Wed Jul 12 00:06:10 2017 daemon.debug pppd[6325]: [service-name]
Wed Jul 12 00:06:15 2017 daemon.debug pppd[6325]: Send PPPOE Discovery V1T1 PADI session 0x0 length 4
Wed Jul 12 00:06:15 2017 daemon.debug pppd[6325]: dst ff:ff:ff:ff:ff:ff src 58:6d:8f:f5:cb:7d
Wed Jul 12 00:06:15 2017 daemon.debug pppd[6325]: [service-name]
Wed Jul 12 00:06:20 2017 daemon.warn pppd[6325]: Timeout waiting for PADO packets
Wed Jul 12 00:06:20 2017 daemon.err pppd[6325]: Unable to complete PPPoE Discovery
Wed Jul 12 00:06:20 2017 daemon.info pppd[6325]: Exit.
Wed Jul 12 00:06:20 2017 daemon.notice netifd: Interface 'wan' is now down
Wed Jul 12 00:06:20 2017 daemon.notice netifd: Interface 'wan' is disabled
Wed Jul 12 00:06:20 2017 daemon.notice netifd: Interface 'wan' is enabled
Wed Jul 12 00:06:20 2017 daemon.notice netifd: Interface 'wan' is setting up now
Wed Jul 12 00:06:20 2017 kern.info kernel: [ 501.359782] mv643xx_eth_port mv643xx_eth_port.1 eth1: link up, 1000 Mb/s, full duplex, flow control disabled
Wed Jul 12 00:06:20 2017 daemon.info pppd[6440]: Plugin rp-pppoe.so loaded.
Wed Jul 12 00:06:20 2017 daemon.info pppd[6440]: RP-PPPoE plugin version 3.8p compiled against pppd 2.4.7
Wed Jul 12 00:06:20 2017 daemon.notice pppd[6440]: pppd 2.4.7 started by root, uid 0
Wed Jul 12 00:06:20 2017 daemon.debug pppd[6440]: Send PPPOE Discovery V1T1 PADI session 0x0 length 4
Wed Jul 12 00:06:20 2017 daemon.debug pppd[6440]: dst ff:ff:ff:ff:ff:ff src 58:6d:8f:f5:cb:7d
Wed Jul 12 00:06:20 2017 daemon.debug pppd[6440]: [service-name]