Yeah I clocked this actually. There were a few of us on the UFO tracking discords watching the flight radar data in real time and the restricted zone popped up with almost no notice, which is unusual even by Dugway's standards. Normally you get a NOTAM a few days out but this one felt reactive, like something prompted it rather than it being scheduled.
Dugway is one of those places that barely gets discussed compared to Groom Lake but honestly it probably deserves more attention. The biological and chemical testing history alone is wild, never mind whatever else they're running out there now.
Anyone got the actual NOTAM reference number? Would be worth pulling the full details. Theres usually a listed altitude ceiling and duration in there that can tell you a fair bit about what kind of activity prompted it.