Early entry MK ADR after opening

[wings91]

If my ADR is at 9:30, can I still get into MK with the early group? I'd like to wander around Main Street.

 

[Queen of the WDW Scene]

All guests can enter and wander around Main Street USA about 1hr-1hr15mins prior to pening.
With a 9:30am ADR you'll be missing out on the golden hours of RD.
BTW even if everyone was held at the WDW Railroad station still with a 9:30am ADR you would have never been let in prior to RD.