I can only see such a group arise out of the armenians since they celebrate Easter with the west and not with their fellow OO's.
Calendars aren't an issue with the Armenians, and as far as I know, other OO's. In fact, the Armenians in Jerusalem are still on the old calendar and do Easter at the old time and no one thinks twice about the fact that we are doing everything at different times.
I also think the Indians here in the U.S. do Easter with the West.
I just don't think the difference in calendars is something that would get the OO's upset. We have a history of diversity in practice, so differences like that are tolerated. I think that is what has saved us from having some of the schisms that have plagued the EO's, like the calendar schism and the Old Believer schism over how to make the sign of the cross. EO's are more used to uniformity, so stuff like a different calendar or a different way of crossing oneself would cause a problem. However, since diversity of practice is the norm for OO's, we don't go into schism over that sort of thing. That's not to say we don't have schisms. Goodness knows, we have our schisms in the OO community. However, it is not over that sort of thing.