Evocation Adept Arcana Unleashed Bug

The Evocation Adept feat is not displaying the correct 'to hit' and save DC values for the feat spells on my character sheet. I am a bard with +5 charisma and proficiency +3 but the to hit roll and save DC are only factoring in my proficiency bonus. So they are showing as +3 and 11 when they should be +8 and 16. 

This has been reported in the Release Issues thread for the book, but they haven't done anything about it yet.

If I had to guess, you choose one of your Spellcasting features whenever you cast one of the spells and use the spellcasting ability of that feature. There isn't an explicit ruling on it, but given that it just says you always have them prepared, that's how I would rule it.