Hanging with the quad cities group this weekend. Temps are predicted in the low 20's.
I had some good success hanging my poncho liner over the hammock ridge-line/bug screen and tying it off underneath the UQ in my early October hang on Lake Three. It will slide allowing side entry and then scooting it up to provide a nice cocoon before zipping in. We will go a few degrees colder this weekend. I will get a good photo and post with report.
What are some of the things you folks have done when temps drop in addition to the quilts?

i have an underquilt protector from 2qzq. it does add some warmth due to it blocks the wind as it completely covers the uq and entire hammock.
also i wear warmer clothes items. i will be winterizing bro in laws cabin, otherwise i would be there, have fun!

I set my tarp up in storm mode(all the way to the ground) and I use a 0 degree sleeping bag that I zip up. These 2 things have allowed me to use a 40 degree underquilt down to 25. I'd be curious about condensation on your set up.

Condensation was a concern I had when planning the idea. The poncho liner, army version, is not long enough to cover the entire hammock and I drape one end over the foot creating a box. There is no coverage directly above my head. So far no problems.

Temps only got to 34 degrees so no new lows for me when hanging. The view shows three ties connected at the foot. The center ties are also connected under the UQ. The top ties are not connected allowing the top to slide or fold back for entry and ventilation.
One day I will upgrade to a commercial cocoon, but this was available.

I sometimes use a nylon sock and below 15F I switch to a cotton canvas sock, which helps with (but does not eliminate) condensation...