Amusement Ride and Tramway (ART) Unit in California is going to need to inspect and approve these modifications before it can reopen.
I wouldn't say the Knott's ride will open first. That statement is pure speculation. In fact, California will be the hardest to reopen because of the state government's intrusive inspections and meddling in the amusement industries business. If it reopens first then everything went well with the state inspection, but the other Cedar Fair parks where these same rides exist won't have to go through the extensive BS that California puts permanent amusement ride operators through.