We do have an Avaya forum, which would give this more visibility.
https://sundance-communications.com/forum/ubbthreads.php/forums/5/1/avaya-lucent


Since you have a backup on the card, do a factory default and test the lines again. If they function properly, your back up is corrupted and you should reprogram from scratch.

If they show the same behavior once the hardware is defaulted, the hardware is bad and you need to replace it

I can recall one site that we restored from the card, it acted funky, was able to connect the old GUI remote programming software, and found phones with 2 line 1 buttons assigned. When you hit the extra line 1 button you would cause the system to reboot.