MLK Day arrival affect room rate?

My wife & I just booked a January 2022 trip (a re-booking of our cancelled 2020 trip), and I just realized that our check-in day is MLK Jr. Day. We plan to take advantage of the regular January “35%-off room rate” deal as soon as it drops —probably this summer— but IIRC, the discount is determined by your check-in date only. And I imagine a federal holiday isn’t going to see any sort of rack rate discount. Is that right? We’re staying at the GF, so 35% off $660/night is a big deal.

If we have to move our check-in date from Monday to Tuesday, we will, but that will screw up our return plans, and we want to avoid that for work-related reasons.

You can check detailed historical discount days/data here: Historical Disney World Discounts - MouseSavers.com