I wouldn't wait for a bleed to start another cycle - doing this can result in undertreatment with progesterone which is needed to keep the endometrium healthy.
You need to take at least 12 days per month of progesterone (unless you are under a specialist and being monitored with scans) or you could end up developing a thickened lining over time which can cause no end of problems.
There are multiple other options which are bleed free if you prefer. I personally am not a fan of cyclical hormone therapy in peri as it commonly results in chaotic bleeding, angst over what cycle day they are on and when to take the progesterone, and can lead to more days spent bleeding overall than untreated women.
If you are under 50 with no risk factors, a combined pill taken continuously can be a better option.