I have two WiFi connections configured - both have the same SSID and connect to the same AP, only the second connection is restricted to the 5 GHz band. The first connection (the 2.4+5 GHz one) has priority 1, the second one has priority 10. Both connections are enabled to connect automatically and all users can connect to them. However, when I reboot the first connection is picked despite the lower priority. I can verify that both connections are set up correctly as I can manually connect to either of them.
I checked this and autoconnect-priority is saved correctly to NetworkManager, which means there is probably a bug in NetworkManager itself. Report please this issue to NetworkManager bugzilla.
Bulk transfer as requested in T17796