I took my WBBB 1.1 dbl and Incubator 20* out for their maiden voyage last night and had the same problem. Even though the temps were only in the 30's I had the "cold shoulder". I was able to reach out and adjust it, but doing that throughout the night doesn't make for a good night's sleep.
My son had it worse. I got up around 6:00AM to check on him and the entire quilt had slid off to one side. He has my old Hennessy bottom entry, so adjustment is a pain. I don't think he even realize it had slid off. It was his first night in a hammock and he froze. Hopefully I didn't turn him off to hanging.
Looks like I need to dial in the suspension. I have the new Incubators that lack the shock cord along the side channel. That will be the first thing I add.
On a positive note, I was toasty warm on top with my 20* burrow.