Week 1 Feels Brutal
Your 1RM is too high. Lower every entered max by 5 to 10% and restart week 1. This is the single most common failure mode and it is entirely fixable.
You Miss Reps in the Volume Phase
Cut one back-off set for that session and keep moving. If it happens twice in a week, lower the 1RM.
The RPE Single Comes In Light
That is fine and it is the point. RPE 7 in week 6 is supposed to feel easy. The program is walking you toward the max, not throwing you at it.
The RPE Single Comes In Heavy
Take the load that matches the effort, not the load you expected. If week 8's RPE 8.5 lands well under your projected max, your entered 1RM was optimistic. Adjust your expectations for week 9 rather than forcing plates onto the bar.
You Are Tempted to Skip Week 5
Do not. Weeks 1 to 4 deliberately bury you. Week 5 digs you out. If you carry that fatigue into week 6, every RPE target inflates and the peak is worthless.
You Miss a Session
Pick up where you left off. Do not double up two training days to catch up, especially in the peak weeks.