Strength phase fitting into the cycle length

I'm currently on up/low split level 7 and I'm 9 workouts before I level up. Today I started a new cycle (with lower body 7A medium workout). After I was finished, the app told me that starting from my next workout, I'll begin a strength phase, as is supposed to happen every time before going up a level.

This is all fine, but why didn't the strength phase start at the beginning of the new cycle, and why it does not fit into the workout schedule as the strength phase is finished at the middle of the cycle? Is It really necessary that the strength phase is exactly 9 workouts long, or would it be possible to program it to fit into the workout schedule?

As the cycle in my current program is 6 workouts (lower body & upper body all have medium, light, and heavy workouts), perhaps the strength phase could take 6 or 12 workouts? And in PPL level 7 program, the cycle is 9 workouts. On Muscle split program, the cycle is 6 workouts long, etc. You get the picture.