The dream school just gets put on hold until the new coach starts recruiting. That may end up just delaying the process, or it may end it. Too early to tell.
I do agree with others about targeting other schools. Since your son has his heart set on the one school, I'd start small. Identify 3-5 other options that he's ok with. Focus on things like location, size, budget, and majors. Talk to the travel coach about contacting those schools. If your son was already talking to a mid-major, then this summer will be important for him to get in front of college coaches.
He will probably be impacted by the tail end of the covid oversupply, but they should be gone by the time he's a sophomore. With that in mind, he may want to consider a juco.
Good luck this summer.