Well, you can start
Autodesk now. There's no check to cash for that.
They freely offer a whole slew of general educational software.
On rare years, FIRST will send out some piece(s) of the Kit early if teams have already paid. But you can pretty much wait until you hear that is happening before you pay early.
The first year of this cRIO control system arrived at Thanksgiving.
School payments do take time to process, so don't necessarily wait until the last minute, but it is easier to wait until after the NASA grants are awarded.