Before the first spin of the session
Five reels and four rows make up the grid, but how often the bonus round comes is not known in advance. Each spin decides which symbols land, so the number of bonus rounds in one session is random. The result of one session is random whatever the RTP. The RTP only describes the return across a very large number of spins.
Three versions of the series carry different RTP figures, and the one Jackpotcity Casino runs is shown only in the game rules. Open the game rules in the lobby before the first spin to see the version in use.
Twenty fixed paylines pay left to right from the leftmost reel, and the maximum win sits at a ceiling that is reached very rarely. Treat that ceiling as the limit of the top prize, not as a target for any one session.