The series I do has a dinner after the 200k, (plus they bring breakfasty things like banana bread and coffee/oj to all) lunch stops for 300,400,600. The 600 regrouped at the host hotel, so the RBA's wife was kind enough to have dinner ready in their room from 4PM on, I mean until 1AM when I woke them up!, and then breakfast again when people left in the morning, from 5AM on, then lunch/dinner stuff in their room when we finished Sunday.

The cue sheets have stores marked on them, at 20-30 mile spacing usually, with the controls at convenience stores. Some people ride these things and only stop for controls. I think the routes, here, are planned taking stores into consderation.

Still, brevets are supposed to be minimaly supported- no SAG vehicles- you need to be able to follow the cue sheet, not get lost, find yourself if you do get lost, and if you abandon, call a friend for a ride home.

If I were you, I'd set my bike up with a rack (I've done fine with a seatpost-mounted rack that only holds 20 pounds or something) and a trunk bag, possibly with fold out panniers. Look at the Topeak site- those bags slide on and off the rack so they are easy to change out, (I have a big one and a little one) and bring in the house, etc.

(Have to go work- will add additional thoughts in a while)