The first, incomplete rough cut of the short weighs in at 6:21. That’s with slugs in place of the missing scenes; the actual running time will of course be different, but this gives a feel for the length.
That’s respectable. The script was eight pages, so it’s only a couple minutes off of what the expected running time would be. Honestly, I was feeling five minutes, so the fact that it’s edited into over six is surprising.