More Sealed Letters?

this theory is not confirmed so ehm i might be worng
ok so there are 15 new relics right? and 3 new kinds of gear known as rings necklesses and bracelets
so since sealed letters only drop from relics with gear in them there might be 3 new sealed letters with more information
or mybe they drop other kind of letters , the thing is that if those kind of relics exist there is a high chance they contain more interesting info :p
well thats it just thought i'd share this theory

 

I am not quite sure, but I think it isn't the case that each relic has its letter.
All armor-relics drop a random letter, and it would also work for the newly added.

 

There is no gear relic in Gavel, so no, no more sealed letters in the relics.