Yeast went on vacation for a week.

[MSweat]

This is the first time I've had this happen.
I have an Oatmeal Stout in the fermentor. Started with an OG of 1.058 about three weeks ago, checked it on February 27th and it was at 1.024. I checked it again on March 6th and it was still at 1.024. So, I'm thinking I might bottle it tonight and when I went to bring it up, I noticed what appears to be a second krausen on top. I watched it for a while and have airlock activity about every 15 seconds. I checked my gravity and it's now at 1.020.
I keep my fermentors in a storage room in the basement that use to be a coal room, it has three cement walls that are approximately 18" thick and I have insulated the fourth wall and ceiling. It maintains a temp of around 68 F pretty much year round.
I guess I'll let it set longer and see what happens.

 

[pkeeler]

Keep an eye on it. Could be some kind of mutated yeast, wild yeast, or bacteria that is doing the fermenting now.

 

[yellowthere]

Keep an eye on it. Could be some kind of mutated yeast, wild yeast, or bacteria that is doing the fermenting now.

No need to assume things like that. yeast are living and are not entirely as predictable as we often think.

Sounds like good news. 1020's was probably a little high.