Can you do a diacetyl rest for too long?

[biestie]

Title says it all. Here's my scenario:

I figured if I'm gonna tie up my freezer at lager fermentation temps, and eventually lagering temps for close to two months, I might as well make two. I didn't really consider the fact that there would be a fair difference in fermentation times between the two beers. (schwarzbier with an OG of 1.051 and maibock with an OG of 1.072).

After 11 days, the schwarzbier is at 1.020, and the maibock is at 1.042. I'm considering 2 options.

1. Pull the schwarzbier out of the freezer, let it come up into the 60s, and leave it there until the maibock can finish its fermentation/diacetyl rest. Then transfer them both to secondaries and lager.

2. Leave them both at 50 degrees until the maibock is ready for its rest, do both of their rests at the same time, then transfer to secondaries and lager.

As I type this, I don't really think it makes a lick o' difference and I should RDWHAHB, but asking if there's an issue with either option just to be sure.

 

[jeepinjeepin]

Leave them both at fermentation temp until they both finish. Then rest and lager both.

 

[Yooper]

I'd be inclined to do the diacetyl rest when the fermentation slows, and keep it at diacetyl rest temperatures until the second lager is ready.

The reason is pretty simple- it seems that the yeast are more readily able to uptake diacetyl when still active. If you wait until FG is reached, and then wait a few more days, the yeast may not be as active and able to digest the diacetyl. I like to do the diacetyl rest when the beer is at about 75% of the way to FG, or about 1.020 in a "regular" lager. In a bock, since the FG may be 1.020, I do the diacetyl rest at about 1.026ish. Once the yeast flocculate, it's harder to get them to clean up diacetyl.