short answer is yes. Info controls may work in some situations, but receipts and store stamps and initials / sigatures are the way to go. Be sure to give some thought to what to do if a store clerk writes in the correct time, but the receipts from the same store has some other time. Most of the mom-and-pop c'stores in North Carolina have the wrong time on their cash registers. The big chain stores almost always have the exactly correct time. We collected quite a few receipts that did not agree with the clerk hand-written times. (I came up with a solution to that problem -- the package of materials we turned in was less than it might have otherwise been -- that's all I'm "saying".)
The rules on the RUSA website are pretty good and comprehensive. Also, I hope you have an amenable RBA. Ask him / her questions.
I took over as team captain last year when the intended team captain just didn't have enough time to do the route planning and cue-sheeting and etc.. I knew nothing. But Dean had the basic idea for the course, so I reverse-engineered it. In our case, the hardest part of that was getting from the outskirts of Raleigh into the middle of town. One of the other riders knew a way. Then, given the "drawn backward route", I created the map and cue sheeted from the start to the finish.
20 miles short? Go off your intended course for 10-miles as suggested by Homeyba to some eats, then ride back to the course. OR, change the start.
The most interesting thing (to me) is the potential for an alternate 22-hour control and an alternate finish (if your course is long enough and you've fallen behind the intended pace). The control card will have extra spaces for those -- confused me for a day, but before RBA Tony could respond, I re-read some of the rules, and sent him an e-mail cancelling the question.
Finally, I admit that I don't really know what I'm doing when it comes to a Fleche --
after all, I've only done one.