I'm working on a bourbon barrel porter. It started out at 1.062 and ended at 1.026 after two weeks in the primary. Despite many attempts to rouse the yeast I wasn't able to knock it down any lower. I transferred it into the secondary, waited a week and added a bunch of oak cubes and 16 oz of bourbon (the oak cubes soaked in the bourbon for 3 days). It's been about a week since I added those and I just noticed that the fermentation lock is bubbling relatively rapidly (1/second) and a slight krausen is forming.
Any thoughts on why this would happen? Is there anything I can/should do?