Find the RTP version in the rules
Each spin drops a new grid of symbols onto the 5x6 reels, and the Free Games Feature can start after any spin. How often it arrives is not known in advance. Nothing on the screen shows the gap between triggers, and the result of one session is random, whatever RTP version is running. A quiet run and a lucky run both come from the same random draw.
The 5x6 reels run one of six RTP versions, and that version sets the long-run return of the stake. Which version we run is shown only in the game rules. Read that part before your first spin, then compare it with the money table on this page.
A round on the 5x6 reels can pay up to x50,000 the current Base Bet, and that cap is a ceiling reached very rarely. The maximum win is a limit on the payout, not a target a session works toward.