Oh I'm a bit easy there. 1/2 hour before they jump for any selection. If any of your selections is a late scratching, you get the SP fav. unless you nominate a sub.
Anyhow, welcome aboard with heartfelt approval. Not many of high opinion here every get on board. Some of those I highly respect because of the way they bet: Chrome, Bagman, Party and quite few others on this forum page just don't suit a betting comp. because they bet lay, or odds just before they jump.