I have 3 nights in a studio booked for this coming weekend and have been stalking the site for a good 4 months to see what may come up. Very slim pickings in availability so I would say your chances are not very good for 4 nights.
I booked a 4-day, 3-night stay at AKL Jambo for 2 weeks ago inside the 31 day mark. If you're flexible with where you're staying, keep an eye out for cancellations. It's not guaranteed obviously but people cancel all the time.
For someone flexible there’s a chance. Highest likelihood is OKW, SSR and AKV (they are huge with tons of rooms) since 4 nights together is hard even at those but has the most possibility. Like maybe a mon and tues at BLT pops up that could be paired with one of those easily for a 2+2 split stay. I think that’s the most likely scenario… you’re able to find 2 nights at one of the smaller resorts around MK/EP and then tack on the other 2 nights in one of those bigger resorts.