There is no formula for when to cash out (from a winning or losing perspective) when you’re counting or just gambling. If you’re counting, the more time you play the more money you make (in the long run) and when you’re gambling, the more time you play the more money you lose (in the long run). You’ve been getting lucky with your wins but mathematically if you played for a long enough time you’d lose it all.

Lets say I played until I made $10. I bet $5 and win, so my session lasted one hand. Now I come back to the same casino the next day and I played by the same rule as above. Now lets say it takes me 3 hands to make the $10. So far I have played 4 hands and made $20, but the time it took to make that $20 was 24 hours (because I left the casino after the first hand and came back to the casino after 24 hours). Now lets start over and say your new goal is $20 made, so you go to the casino, you play 4 hands in 2 minutes and you won your $20 in one session. Now you’ve won your $20 in 2 minutes instead of 24 hours.

so my point is: it doesn’t matter how long your sessions are, they are all one long session, and for your long session as a gambler, you’re losing money every hour, so the less you play the better.