Krausen won't drop

I brewed this saison about a month ago on 4/14/13.

Pilsner 9#
Crystal 20 .5#
Munich 1#
Vienna 1#
White Wheat 2#

Northern Brewer AA 10.6% 0.5 oz
Styrian Goldings AA 3.4% 1.0 oz

Yeast White Labs WLP565 Saison in 4 cup starter.

SG 1.050

I fermented cool, at about 63F, because I keep my house cool at that temperature.

When gravity reached 1.020, on 4/20/13, I added a vial of WLP007 Dry English Ale yeast, because I wanted this beer to finish very dry and I noticed that WLP565 is not a particularly attentuative yeast.

I also raised the fermentation temperature to about 72F.

By last weekend, gravity was down to 1.009. and I let fermentation temperatures drop slightly. By Thursday, it was 1.006, which is where it is today. So it appears fermentation is complete.

However, there is still a krausen on the beer. Normally, krausen is pretty much gone as fermentation approaches completion.

So my question is this: do I go ahead and cold crash this beer now, or should I let it rest at room temperature longer until the krausen drops? Is it normal for this yeast to have such a long fermentation? (Usually I can crank through an ale in 2 weeks.)

Subsribed

WCB

Let it set, it my take another week or another day before it drops, but it will drop. I have an ale I brewed using Chimay yeast, it took about another week after fermentation was done for the krausen to drop.

Thanks.

With 2# of wheat in there, that's a lot of protein, so you've got that persistent fluffy head they talk about in the style guidelines. You're at 88% attenuation going from 1050 to 1006. I wouldn't worry about the krausen not dropping. If you absolutely have to have it drop, you can rock or swirl the carboy lightly and it should drop out for you in about 24 hrs.

It sounds like an outstandingly dry saison