Just a brief bump to see if this is being looked at and if others can contribute any information to this re: other divine feats (shieldmaiden's etc) and other combat modes. I know we have a plethora of paladins parading about right now, and with the duration of combats and the inconsistency of reapplying Expertise this is a pretty severe point of pain.
I did test this somewhere with traditional full action DM/DS, and it wasn't dropping Expertise, so I'm not convinced this is a Beamdog issue. It also cropped up shortly before the Big Update, rather than after.
Edit: I remembered that I have power attack buried away somewhere. The DM/DS don't cancel Power Attack, only expertise.