Once a week boil on divided pan

[berkshires]

This will be my first full season using my new Mason 2x3. Previously I did batch boils on a small homemade evaporator.

I live two hours from my sugar shack/sugarbush, and I have family responsibilities. So I really can't get to the rig mid-week. When I was batch-boiling, I would just boil everything down as far as I could, and then finish on the stove at home. But that doesn't make sense with a divided pan, so I'm trying to make a plan. Here's what I've come up with so far:

Early season:
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1 - At the end of the boil, stop feeding the arch. It'll still be hot for a while, but not raging hot. Slowly open the syrup spigot while feeding fresh sap from the preheater into the pan, until I have caught all the nearup that was in the last channel. This goes into container #1 that I will boil down to syrup at home.
2 - Continue to catch another gallon or so of boiled sap into container #2. This should be halfway to syrup, and I'll put it in the chest freezer when I get home.
3 - Close the spigot and dump the rest of the sap from the preheater into the pan. Make sure it comes to at least a simmer, and make sure there's close to an inch in there, so it doesn't cook too much and burn. Then cover with foil and leave it to freeze.
4 - Next week, a couple days before I head up to boil, take container #2 out of the chest freezer and let it defrost.
5 - When I start up the evaporator, after all the frozen sap in the pan has melted, pour the halfway-to-syrup into the syrup channel. That should set up my gradient.

The one thing I'm most worried about with this method is that the dividers in the pan are just tacked to the floor of the pan, so if the frozen sap expands under the dividers, could it warp the pan and open up the space between the pan and the divider more and more every time it freezes? Maybe even pop the tacks?

Later season, or any week with warm temps predicted:
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1 - Same as above
2 - same as above
3 - same as above
3.5 - After the fire has died down enough to be safe, take the pan off the arch, and dump all the remaining sap into big container #3
4 - same as above, but now with two containers
5 - Same as 5 above, but instead I fill the pan with container #3 first, then pour container #2 into the syrup channel of the pan

My big concerns here are being able to handle all the sap in the pan at step 3.5. I have to get the timing of stopping the fire just right. If the fire is burning too long and hot, I risk the level getting too low and burning it, or else taking the pan off with a raging fire and burning down the sugar shack and scorching myself! If the fire dies down too soon, then I have too much sap to deal with, and may not have a way to get it all home, or be able to store it all until the next week.

Anyone else been in this situation? What did you do? Or if you have a divided pan and could only boil on weekends, what would you do?

Thanks for any input!

Gabe O