I have had similar but not exact thing happen to me in the past, unless you are 2 nights away from the next milestone I suggest you just let it go. In the past I actually had them extend my reservation 1 night because they messed up how they charged me (I had booked points + 100 to upgrade, and long story short, they still charged me the $300 but made it an extra night). In my case I was extremely happy with the end result since I got an extra EQN and I had a promo for 1 FNC with every paid night, which this stay would have otherwise not qualified me for.

In other words, you win some you lose some. I am sure you have had other situations where the hotel messed up and it was in your favor, it happens both ways. You take the good so you need to take the bad too. I understand its frustrating, but it is what it is at this point. I think the hotel probably meant well by moving the reservation and now it might be too late.

If you do end up needing the nights, the points received should at least get you 1 night at a suburban Fairfield Inn. Go on a one night free getaway, enjoy the pool and free breakfast as a reward for your trouble.