Mare heat cycle

[Lifedaybyday]

If I have a mare who foaled April 15th and was in foal heat around the 26th of April ( which we skipped and chose not to breed) When can I expect her cycle to come again? New to this and trying to figure out these calculations.I did not own her at the time of foaling or during first foal heat so any help in appreciated.I don't want to miss the window.

 

[Taz]

They normally come in for about a week then out for about 3 weeks. So count from the day she last went out.