How soon will the bonus round arrive?
Symbols land on the reels at random, so how many spins pass before the bonus round appears is not known in advance. One session can bring the feature early or leave it out entirely. The RTP describes the return over a very large number of rounds, not the result of the session you play tonight, which stays random whatever the RTP is.
The reels never reveal which RTP version runs in this lobby. That detail appears only in the game rules, so read those before staking real money. Big Bass Splash belongs to a series of versions, each with its own RTP, so check the exact title on the rules screen before you compare numbers.
Each combination on the reels can pay, but the maximum win is a ceiling reached very rarely. Treat it as the top of the scale, not as an expected result. Reaching it depends on the same random outcomes as every other spin, so no session plan will bring it closer.