When does your ewcm start before ovulation?

Ch
Hi! I'm just wondering because I usually ovulate anywhere from cd 16 to 19, but I'm on cd 12 and had a gush of it this evening and yesterday my sex drive was sky high. We're only going to be able to do the deed tomorrow evening because we have family coming :/. So I'm hoping I'm close enough but not so close I can't wait until tomorrow. What do you think?