I've got a lower 3rd, created in after effects, then exported and used several times in Premiere Pro.
The first line of text has the font as all caps.
This works in AE, and Looks fine in Premiere. It Previously even worked in Media Encoder.
Suddenly (probably after the latest AE update), the titles are staying all caps, Except for "h" and "v". There could be other letters, but of the few names, those are the two letters that it happened to.
It only happens in Media Encoder, so seems related. If not, well, it's still a bug that Adobe should look into.