Book of the Fallen results stay unknown in advance
Before you set a bet, accept that the bonus round does not arrive on a schedule. How often Book of the Fallen triggers its free spins is not known in advance, and no session can be planned around it. The result of one session is random, whatever the RTP version you play.
Check which RTP version is live before you spin. Picklebet Casino runs one of the three RTP versions of Book of the Fallen, and only the game rules state which one. The figures in the table on this page show what each version pays over a long run, not what one session returns.
Treat the top prize as a ceiling, not a target. Book of the Fallen caps a win at 5,000x the total bet. That ceiling is reached very rarely, and no one can say in advance whether a given session will come near it. The maximum win is the highest possible payout, not a figure to expect.