If someone is interested in open hardware running openwrt, also check out Turris. https://www.turris.com/en/ I have been using them for years and I'm really happy. I recently bought the WiFi 6 upgrade kit for both of my turris. They "recently" released their latest version which is expensive but comes with WiFi 7 and 2.5 Gbps RJ45 and 10 Gbps SPF.
Are you certain this is running OpenWRT? As in, can I get a OpenWRT build and flash it to the router and have it work?
Last time I checked (a couple years ago), it seemed that I could use OpenWRT but I would lose some functionality (was it the FTT maybe?).