Surplus of hay

So I am coming up on a surplus of hay and a neighboring property wants me to bale their property on shares for years to come. I have cattle that I have always sold calves at about the 6 month mark. I have been producing quality hay and very much so limiting buying feed. And by doing so i took a herd of 3-4 BCS heavy breed cows last year to 4-5 BCS mostly 5s by just way of grass and hay(it was also a very dry summer and all cows had caoves on them during drought).
So my tgought it with having a surplus of hay could someone keep bulls calves and cut them at 6 months and keeo back quality heifers and put them on pasture(limited) and feed alot of hay and put weight on them for 3-4 months with a stockpileof 12-14% protein hay? Or is it better to just sell them? I know i could give then free choice hay with feed but not sure that would work out money wise. Just looking for yalls thoughts. Would be from about 160 head of cows. Just looking for a way to make a little more from the herd and use up some hay. Also probably be best to just sell the hay???

Surplus of hay