Regen formulas changed in 2.1 (some are now additive that were multiplicative) plus you lost your Emperor bonus and I'm reasonably certain the drink bug not stacking with CPs was not yet fixed.
Edit: confirmed it still is not stacking with CPs. For me at least this is another 120 or so Stam regen and 25 magick regen.
Regen formulas changed in 2.1 (some are now additive that were multiplicative) plus you lost your Emperor bonus and I'm reasonably certain the drink bug not stacking with CPs was not yet fixed.
Edit: confirmed it still is not stacking with CPs. For me at least this is another 120 or so Stam regen and 25 magick regen.
I wonder if that was intentional.