You are absolutely correct. I tried this with copying some of mine in the company file and sending them to myself and that worked.
But I don't want to have to do 400 all over again. Per my conversation with support today, The next update for a fix on this will happen end of day 7/6. So I am waiting.
Good to know you can go to the list>edit>duplicate and then remove the old one and it will work.
Fingers crossed when the next fix comes, they work again.