When will the free spins start?
The 7x7 grid holds 49 cells, and no figure on this page can tell you how often the Free Spins round will start. That frequency is not known in advance. The result of one session is random, whatever RTP version you play, so a short session can end well below the stake and a long one can end above it.
Three RTP versions of Sugar Rush 1000 exist. Only the game rules show which one Retrobet Casino runs, so read them before a session if the difference matters to you. A small gap in RTP means a small change in the long-run average, not a change in what any one spin pays.
The ceiling of 25,000 times the bet is reached very rarely. Whether any session comes near it cannot be known beforehand. A win at that level is one event, and the money it pays depends on the bet placed when it lands.