2500 hours in 9 months could be two developers logging hours on the project. The project may have had stretches when dependencies limited the amount of work that could be done, and often one assumes at least an hour of non-billable time lost to miscellaneous business shit, per IC, per day.
The rest of the team (not logging engineering hours) may have included a (probably part-time) designer and likely some kind of project manager (likely also part-time—that is, managing 2+ projects at once for different clients).
7 (billable, on average) hours * 47 weeks (assuming 25 weekdays lost to holidays, sick days, and vacation, over a year) * 5 weekdays only yields 1,645 hours per worker per year, anyway. Divide by four, times three, to get ~9 months, and 2500 hours just looks like two full-timers on the project, really, if we're talking billable hours, but that's also (it reads like) not counting support roles and non-dev contributors like design or PM or maybe testers. Or it might be one full-time and two half-time devs, or whatever. I'd guess not more than four developers contributing significant time, anyway, based on the numbers and with fairly pessimistic assumptions for how many hours could be logged a week, and maybe as few as two.
The rest of the team (not logging engineering hours) may have included a (probably part-time) designer and likely some kind of project manager (likely also part-time—that is, managing 2+ projects at once for different clients).
7 (billable, on average) hours * 47 weeks (assuming 25 weekdays lost to holidays, sick days, and vacation, over a year) * 5 weekdays only yields 1,645 hours per worker per year, anyway. Divide by four, times three, to get ~9 months, and 2500 hours just looks like two full-timers on the project, really, if we're talking billable hours, but that's also (it reads like) not counting support roles and non-dev contributors like design or PM or maybe testers. Or it might be one full-time and two half-time devs, or whatever. I'd guess not more than four developers contributing significant time, anyway, based on the numbers and with fairly pessimistic assumptions for how many hours could be logged a week, and maybe as few as two.