I think day 15 is really hard for one day comparing to other days. Seven Geometry chapters in one day, comparing to other days where there are two there chapters, Chapter 6-7 in Manhattan relatively tougher.
You actually have 2 days (days 15 and 16) to complete all of the Geometry content.
If any days seem overly heavy, don't worry. You can always take longer than a day to complete the activities. Plus, later on in the Guide, much of your time is spent working on weaknesses (i.e., not learning new content).
I hope that helps.
Cheers,
Brent
