I brewed a Milk Chocolate Stout 7 days ago with a starting gravity of 1.072. Using a double yeast pitch of White Labs London Ale 013, the fermentation started aggressively after 12hrs. However, after 48hrs since the yeast was pitched the fermentation slowed to a halt. I'm on the 7th day and the gravity has been 1.026 for two consecutive days, which is .009 higher than expected.
Should I wait it out a few more days or maybe pitch another vial? It's winter here in Chicago so the carboy has been kept on my kitchen table with the house temperature steady at 70-72 degrees.
Never brewed a higher gravity beer like this one so any advice would be helpful.