HP I am going to base my answer on my location which is north of Kansas City, South of Fargo, West of Cleveland and East of Laramie.
Not being a smart a-- but I do know the Xenpro forums has viewers in the millions and I cannot attest to any one's individual motivation.
That said, I put the bull with the cows Jul 1 which will give me calves starting April 5. With 20 head they will usually be done by the first
week of May. I seldom have no more than 3 replacements and sometimes none in any given year. When I do have replacements I will
put the bull with the heifer say about June 10 or so. That can give me a calf as early a 15 March but seldom if ever have 3 calve in March.
What am careful about is making sure the bred cows are getting good rations , including minerals and supplements, so I have more assurance
they will breed back in a timely manner. The heifers are fed with the market calves which normally are sold at 10-11 months 870 lb mosa minos.
which would be late March early April. ( I should have indicated especially the 3rd trimester for the bred cows)
I suppose calving in the fall can give one an advantage in some markets in which case I can see your reasoning. Of course location is always
a factor as well. I used to calve in February and March and I remember going out to check cows in the dark with a flashlight.
Anymore I go out in April and count calves . You are in a very good position to be insured of a short calving period if you are using AI.
I think I would just breed the heifers a cycle ahead of the cows separate them from the cows until the cows were done then put them together.
(Heifers can forget which baby is hers or vice versa......) If I had just one and it were off cycle I think I would butcher or trade it in for new model....
Main thing is '' drive your own bus and do what works for you''! Hope your winters are warm!