Again here are the rules:

If we measure your current top speed at 60 bpm or below, you have to play faster than 120 bpm on the last day, to be eligible for the refund.

If you play at 80 bpm or below, you have to play faster than 160 bpm.

If you play faster than 80 bpm, you have to simply double up.

If I catch you faking something, you will be excluded from the challenge.