I've check that Trash Bin MOD install those 4 columns on phpbb3_posts:
post_deleted_from, post_deleted_user, post_deleted_time and post_deleted_reason.
phpBB 3.1 incorporate a SoftDelete system. And it was added new columns named:
post_visibility, post_delete_user, post_delete_time and post_delete_reason
And I've check all files from 3.1.11 installation and even 3.2.1 installation and I discover the following:
That there is a file on the updater (v310) that will Convert an OLD MOD:
And this .php file that convert this, is messing with all people that have TrashBin MOD instead of SoftDelete MOD and try to upgrade.* Migration to convert the Soft Delete MOD for 3.0
So, I guess phpBB should have a system that would detect if SoftDelete MOD is really installed or TrashBin, and convert it accordingly. Or atleast don't run that code if SoftDeleted MOD is not installed!
And people with TrashBin doesn't even have the option to choose to not run that convert option that is ruining everything...
And I was going to download SoftDelete so I can see which columns that mod use, but I can't open the page of the MOD. It gives me: " PHP Warning: in file [ROOT]/phpbb/di/container_builder.php "
PS: Ofc, I've a quick solution as rename those columns temporarely before the upgrade. And then rename them again so I can run some SQL code, to convert TrashBin to phpBB 3.1 SoftDelete System. But it would be WAY better that phpBB help people out on this, and not creating this issue.