Twitter Import Despite Syncing Turned Off?

[bradl]

I have import status for facebook/twitter turned off. Yet I have a member who's legit tweets are appearing from time to time as status updates. The person does not appear online ever, nor in the Who's Been Online list at any time, so it seems like these tweet-based statuses might be automatically generated somehow.

I don't get many twitter-based sign-on users so little experience here. (I'm not really sure that's how they registered/signed-in either. The user has been a member since 2014. I only correlated to twitter based on the avatar and matching tweets.)  This appears to be a very recent phenomena (the first instance was the day I upgraded to 4.1.9 but that could be purely coincidence)

Any ideas?

[bradl]

Group permissions are set thusly:

If I log in as the user I see the following under their account settings / twitter:

It seems like the profile sync happening "periodically" may be what's posting the status update. 

If I select Disassociate Twitter for this user does that in any way break their ability to log in or use the forum using their twitter credentials? Or does it simply stop the sync from happening and skip avatar changes and similar twitter-profile-updates?

If I can't stop the status syncs from happening, what happens to users who have accounts based on Twitter if I disable the Twitter login handler at the ACP?