As a casual bystander this year, I could see all those being valid.
Most could hear by 15th. Especially if waitlist drop was today. In previous years the main TWE drop came a couple days later.
With medical potentially being delayed, there could be many slates still unresolved. Maybe there are 2 competitive candidates for those slates that wouldn't necessarily be competitive nationally, and USNA is having to wait for resolution and is prepared for those decisions to run till end of Month or later. .Just my guess...