That’s actually a fascinating idea. All interstellar travel is based on the movements of the planets through space time. I bet it alternates between being technically faster and slower than FTL travel since you may have to wait for a time when your destination to pass into the planets past location.
Wow that’s a fun thought hole. Constraint certainly breeds creativity!
The other thing I noticed up there is that it says “MAR added MAR”. Not sure if those are two people with the same Signal/Contact name/intials, or how that happened (as a Signal user, best guess is group link but that is also would be in the log at the top)