This is something I've pondered w/out coming to any solid conclusion...
Back in the days of break-in oil it made sense to leave it in for the specified time until first change. Now that break-in oil isn't commonly used it's a different deal. But...
My concern with changing early, and not again until the next prescribed change is this: can I be sure that the lubricated parts are done shedding their wear-in crud at that arbitrary early change time? If the first change is due at 50 and I change at 13 out of an abundance of caution, and then the parts shed more junk into the oil until 40 hours, and I don't change until 100 - have I done more harm than good?
Me, If I change early I'm also changing at 50 or whatever the specified break-in change is. But that's just me...
Not sayin', just askin',
Z.