My thoughts since I am not there to actually see her... with the having to feed due to the fire and loss of pasture, cut her grain to just a miniscule amount when you pull the other calf.... feed her just enough so she stays friendly and coming to you... and make sure the other calf can get in for creep so it does not go backwards. Her milk will slow down and then when you pull the other calf, don't feed any grain at all... She should dry up without a big deal since she is not getting any supplemental feed, just hay. You might want to milk her once a day for a few days after pulling her calf, IF, she looks especially full, to take off the pressure.... but 99% of the time we just stop milking and by 48 hours the hormones that kick in to produce milk, stop since there is no stimulation to make the milk.
The only benefit to your loss of pasture is she should dry up easier with no nice green grass to "help with production"...
Some of my dairy farmers that have cows needing to go dry and that are still producing alot of milk, will put the cow in a separate lot and feed only hay and water for a week or 2, then milk them out to make sure there is no mastitis and then dry treat. That said, I have a couple farmers that still do not dry treat, and I have never dry treated my own family/nurse cows...... well, except one that was a chronic mastitis problem and I did dry treat her after the 2nd lactation and it seemed to do the trick as she never showed any clinical signs of "junk" in her milk after that. I didn't milk her for the house at all either... and the constant nursing by the calves seemed to take care of it... The dry treating has benefits for commercial farms with a high concentration of cattle in smaller areas but most people with their small family cow operations do not treat.
Also do not feed her your "best hay"... feed her just some average hay so that there is no extra "nutrition" in it to encourage her system. Whatever hay you are feeding your dry beef cows is fine... she will be in a "holding/resting" pattern just like them... you do not want her to be gaining too much weight or getting fat, but you want her to maintain her condition and maybe gain a little....rounding out and then when she comes fresh, you will start feeding her more and better so she can feed a few calves and make milk for you too.
Thanks for the advice. I think that's what we will do. Good to know her milk will slow. When y'all dry up your nurse cows do you do anything special? Normally when we wean beef cows they just dry up on their own. Dairy cow books and a dairy cow forum make a big deal on doing a whole bunch of stuff.
