Birth control for half cycle?

Brookelyn

I am currently cd1. I have a 2 week vacation planned right in the middle of my cycle. My RE told me to take Birth control from cd1 and stop cd13 and wait for my period to come. I’ll be back cd14 from vacation and we’re starting back up with <a href="https://glowing.com/glow-fertility-program">iui</a>. Anyone take bc for only half their cycle? How long did it take af to come once you stopped?