I determined the flippoints for my mount; 24 minutes past meridian the mount flips from East to West when it receives a slew command. And I determined my mount can't track after the flippoint.

So I'm running a session with 20min Ha exposures, and I noticed this:

[flip check: Tn=1260s HAc=64s GW=F HAz=1331s DWz=T WF=YES]
(GEM must flip before next operation)
[FPw=1440s FPe=-1440s HAt=71s PFM=300s]
(waiting 1669 sec to pass flip limit)
(wait ends at 21:13:46 UTC)
(turning tracking off)
(wait finished, resuming tracking)

ACP needs 1260s for the next exposure... And it decides to wait 1669s to flip the mount. Why? There's plenty room for the exposure...