I can't see any difference in the next betable race starting in 20min or 3 days. They are not linked in any way. Not by luck, profit or loss, chance or anything else.

Sound punting logic and practice would be to choose the races from a card worth betting in [there will be only 3 to 4 at most] and as long as a reasonable SP price is available, bet personal selections in those races win or lose.
If losing, reconsider the SP prices being accepted and/or selection process.