So.... they're Old Calendarists?
Not exactly--they are on the Old Calendar but are not Old CalendarIST as in contrast to the GOC of Greece. Arch. Stephen's ordaining bishop (Timotheos Athanasiou) ultimately has his hands-on-head apostolic succession through the Living Church and Ofiesh. Timotheos's ordaining bishop was Joachim Souris, who went to Greece in the 1960's I believe and proclaimed himself head of the Old Calendarist Church...naturally we Old Calendarists do not accept this interloping as we already had a Church in Greece and Souris was ordained by people that were not Old Calendarist by any stretch of the imagination.
That being said, Arch. Stephen is a kind man and for what it's worth he is upfront about his status and why he is where he is. He's not like some of these people who try and pretend they are accepted into communion by SCOBA and "prove" this by posting photos of themselves with various SCOBA bishops, and who ordain anyone that walks in off the street, etc. One may disagree with with him about some of his positions (he and I have had several friendly exchanges on matters ecclesiological), but he's not trying to pretend to be a recognized SCOBA hierarch or trick anyone.