[Eugenia Gabrielov]

If you are deeply concerned, contacting the planning committee is your best bet. Here are a couple other things you can try:

If the event is at a university, there is a high probability that it will be near the school's spring break when athletic teams and events aren't using the facilities as much as they normally would.

If the event is at any sort of conference center / stadium, they may have a calendar of events for the year that lists FIRST as some sort of conference or competition (generally listed as open to public).

It may be wise,though, to have a couple back-up plans ready in case the dates you want really really don't work out - somebody mentioned Easter as a mid-competition season big holiday, that is definitely something to look at.