I seem to be running into a bug when I report multiple fill-ups on the same day. What happens is that the program is treating the latest fill-up on a given date as the *first* fill-up on that date, for calculation purposes. For instance, if I fill up with Exxon in the morning and Sunoco in the evening, Fuelly thinks that the Sunoco fill-up came first. The only way around this that I have found so far is to report same-day fill-ups on different dates, which is not as elegant as I'd like.
Yep, that would be the ideal solution. In fact, I found that a way around this issue was to add times to my Excel spreadsheet before importing data, and then a 3pm fillup gets recorded before a 6pm fillup, for instance.