Defunct test
I’ve just had a run through and encountered a similar/the same issue:
- Create topic
- Topic wrench → make private message
- Invite a group
- A member (though not the OP) gets removed by the system.
However, replying to the topic still sends the removed user a high priority notification, which seems to suggest they’re not ‘removed’ removed.
Edit: I mucked up the Test_Users in the Group, and borked the test. My apologies. I will try a clean one.
Fresh test (This time making sure my group user was not part of the original topic 
)
This time I used a TL1 test user as my OP, rather than admin.
- Create public topic as TL1 user
- Convert topic to PM (as admin)
- Invite Group (as admin)
- OP gets removed, and no record is left. User does not receive notifications about replies
I’m wondering if it’s because that test user doesn’t have permission to speak to that group? I’ll have another pop.
I’ve lost myself in this a bit, so may have to go and have a lie down, but it seems to lose the OP at the point of topic->PM conversion:
The OP has no record for that topic in topic_allowed_users