Not much to discuss, 7 days after a heat take to your Embryologist and let him decide if the CL is good enough to try a egg. You can do 12 hours either way of a heat to work. Meaning if you have a Friday scheduled you can use Thursday night and Saturday morning heats as well. Sometimes I will go 24 hours if a good hot heat, but always let the ET guy know the heat dates so he can decide on the CL.