Layering/Punch in & out on Cymatic U24

First time poster. I skimmed the forums for this topic but found nothing, please redirect me if this topic has been discussed previously.

When arming the U24 to record I can choose between the following options :

Stereo (Tracks 1&2)
4 Ch (First four tracks)
8 Ch (First eight tracks)
12 Ch (First 12 tracks)
16 Ch (First 16 tracks)
20 Ch (First 20 tracks)
24 Ch (All 24 tracks)

How, if at all possible, would I punch in the middle of track 12 (lets call it a lead guitar track) to replace or comp a solo?
For how useable this product is I will be very disappointed if simple layering and punching in is not within this devices’ possibilities.

Im working on a demo for a band and the recording approach is going to be layering.
Start with recording guitar scratch tracks, play those back to the drummer thru headphones while we record the drum tracks.
Re record guitars and bass, then finally add vocals last.
Without the option to record a single track, how is this possible?

Any insight is greatly appreciated,
Kyle