Disney would be thrilled to have that problem. You really think they will use anywhere near 35,000 rooms? I think 35,000 includes the Swolphin as well as the partner hotels which aren’t guaranteed to get priority. Disney owned including DVC is closer to 30,000. Whole resorts will likely not open and floors or wings of others will be shuttered. It’s possible they use less than half those rooms upon opening. It’s quite possible that CSR is used by the NBA and maybe the All Stars stay shuttered as well as part or all of POR and/or YC. That’s as many as 10,000 rooms out of service. Available Disney owned rooms could be down to 20,000 or less and it’s a pipe dream to assume 100% occupancy even of that.
Assuming they open with a very low 15,000 per park capacity that’s 60,000 people that can be accommodated in the parks. Let’s assume nobody goes to Universal, Sea World, Legoland or anywhere else off property and nobody spends a day at the pool either. If each room averages 3 guests they have enough park capacity to fill 20,000 rooms before running out of park capacity. The lowest capacity number is also not guaranteed to last very long. I know for Shanghai they said they would ramp up a few thousand more people every week. Could there be issues between parks when they first open...maybe so. MK and DHS are likely to have more demand.