other files (passwords, files elsewhere, etc survive the reboot, but the standard files in /etc/config are getting reset
tp-link c2600. I just downloaded the sysupgrade image and reflashed to verify the problem isn't just a bad config. other configs (/etc/openvpn /etc/modules-boot.d for example) are not touched.
~# cat /etc/openwrt_release
DISTRIB_ID='OpenWrt'
DISTRIB_RELEASE='21.02.1'
DISTRIB_REVISION='r16325-88151b8303'
DISTRIB_TARGET='ipq806x/generic'
DISTRIB_ARCH='arm_cortex-a15_neon-vfpv4'
DISTRIB_DESCRIPTION='OpenWrt 21.02.1 r16325-88151b8303'
DISTRIB_TAINTS=''
ls -ltr /etc/config
drwxr-xr-x 2 root root 0 Jan 1 1970 old
-rw------- 1 root root 1000 Nov 16 2020 dhcp-opkg
-rw-r--r-- 1 root root 808 Nov 18 2020 dhcp-orig
-rw------- 1 root root 2287 Feb 3 2021 mwan3
-rw------- 1 root root 840 Feb 3 2021 vpn-policy-routing
-rw------- 1 root root 16714 Sep 1 21:19 openvpn
-rw-r--r-- 1 root root 788 Oct 24 09:01 ucitrack
-rw------- 1 root root 167 Oct 24 09:01 rpcd
-rw------- 1 root root 4632 Oct 24 09:01 firewall
-rw------- 1 root root 134 Oct 24 09:01 dropbear
-rw-r--r-- 1 root root 714 Oct 24 09:01 wireless
-rw------- 1 root root 783 Oct 24 09:01 uhttpd
-rw------- 1 root root 885 Oct 24 09:01 system
-rw-r--r-- 1 root root 0 Oct 24 09:01 ubootenv
-rw-r--r-- 1 root root 862 Oct 24 09:01 luci
-rw------- 1 root root 959 Oct 24 09:01 dhcp
-rw-r--r-- 1 root root 2578 Nov 27 07:24 openvpn_recipes
-rw-r--r-- 1 root root 687 Nov 27 07:24 luci-opkg
-rw------- 1 root root 824 Dec 23 22:12 network
(network was manually edited by me just prior to doing this ls), it boots with the date of Oct 24 2021 9:00