Gaming insurance around childbirth

TLDR can I switch plans to a lower out of pocket max plan after I give birth, and then switch back for the new plan year?

I am currently on an HSA individual plan, and anticipate I will meet my individual out of pocket max(4k) and possibly also the embedded out of pocket max (6k) with my own individual charges for childbirth.

I give birth late in the year,, a little after open enrollment for my employer closes.

In the simplest scenario, I add kiddo after birth to the same HSA plan, I meet my embedded OOP max, but then also have to meet his deductible (1.5k) before insurance kicks in for him. If he has an expensive hospital course, I would potentially be on the hook up to the family OOP max of 8.5k.

But the non-HSA version of my plan has a considerably lower deductible, of course, and ONLY has an embedded OOP max of 6k, no family OOP max.

I obviously chose the HSA plan because it saves me money, taking into account marginal tax rates, premiums, etc. I usually would not even meet the deductible. I would want to resume the HSA plan the following plan year ( about a month after birth.)

Is there any way I could pull this off? I would lose the opportunity to put 2.5k additional into the HSA on behalf of kiddo if I did this, at a marginal tax rate of about 30%, which discounts the savings somewhat.