I’ve used the FPP both ways - getting all sets in in one workout and also spreading them out over the course of a day (especially as the reps get higher). When getting them all into the same workout, I usually “rest” with other work. In the end it often ends up leading a circuit of sorts.
For example: 1 set of pull ups, pistol squat practice, OAPU practice, 10 1-handed swings alt arms EMOM for 10 min. Then start round two with pull ups again. Depending on what I’m doing in that day’s workout, my rest between pull up sets may be anywhere from 3-15 minutes.
And I may be wrong but I feel like GTG tends to be more 1 or 2 reps each time throughout the day versus the specific reps prescribed with FPP.
Of course the hardest part of spreading them out over the course of the day is remembering how many sets and what reps you’ve already done.