[Jon Jack]

Actually, I don't think event dates can be officially released until ALL the regional dates are set. The reason being venue availability. For example, if Regional A uses Venue A and it's available on weeks 2,4 and 5, and is set for week 2; and Regional B uses Venue B and is available week 2 only then FIRST may switch Regional A to a different week and put Regional B on week 2.

They officially release regional dates as soon as ALL the regionals are set. This is probably for the best. Imagine setting your travel arrangements for Regional A, only to find out later that it's been moved to a different week. I imagine FIRST would get some pretty ugly phone calls from frustrated teams if they released regional dates without all the regionals being set.