Ideally the weight would remain the same - but what is more important is sticking to the RPE - which sometimes means dropping the weight (which is okay). Make sure to read the Ebook part of the Bridge as I believe they touch upon this.
TLDR: Dont overshoot RPE, try to stick to it as much as possible - even if that means lowering the weight by 5% or so to keep to the prescribed number across working sets.
You should aim to keep your RPE about 8. If it creeps up to 8.5 and with your shorter 3 minute rest breaks it is likely to creep up again to 9 in the next set, I would drop the weight a little (say circa 5%). It is a battle with the Ego. Remember, Ego is the enemy.
This is more likely to happen in the case of 3 minute rest periods, unless your conditioning is amazing. If you were keeping to 5 minute rest periods you could probably keep the weight the same and only get minor creep to say 8.5 in the last set.
To add a question on top of this if you all don’t mind… when it says say 5@6 5@7 5@8 3 sets. Do you also wait 5 minutes between the sets of 5@6 and 5@7? Or are those still considered warmup sets?
I usually don’t rest between sets up to the @6, just whatever time it takes to change the plates/weights. Then I will change the plates/weights for @7 and maybe have an extra minute. Then after @7 I will take the full whatever planned rest time. So in The Bridge I rested 4 to 5 minutes between @7 and @8, and every set thereafter. In the GPP Hypertrophy, I wait 3 minutes tops between @7 and @8 and ever set thereafter.
I see some of you did the hypertrophy program, I used to do 5s with 5 minutes rest with 0,5 increase in RPE more or less per set (bad conditioning, getting better)
But now 6 reps at 4 mins rest i’m having trouble to find those 6@8x 2 sets or 6@8x3 sets