Having said that, with the information on the surface, this is a completely different situation than with the FI.
The situation with FI was covered by SP Article III:
Art. 3. If communities of Institutes of Consecrated Life and Societies of Apostolic Life, whether of pontifical or diocesan right, wish to celebrate the conventual or community Mass in their own oratories according to the 1962 edition of the Roman Missal, they are permitted to do so. If an individual community or an entire Institute or Society wishes to have such celebrations frequently, habitually or permanently, the matter is to be decided by the Major Superiors according to the norm of law and their particular laws and statutes.
However, as far as I can tell, this Fisher-More issue is an issue of a secular community and, thus, would be covered by SP Art II/IV:
Art. 2. In Masses celebrated without a congregation, any Catholic priest of the Latin rite, whether secular or regular, may use either the Roman Missal published in 1962 by Blessed Pope John XXIII or the Roman Missal promulgated in 1970 by Pope Paul VI, and may do so on any day, with the exception of the Easter Triduum. For such a celebration with either Missal, the priest needs no permission from the Apostolic See or from his own Ordinary.
Art. 4. The celebrations of Holy Mass mentioned above in Art. 2 may be attended also by members of the lay faithful who spontaneously request to do so, with respect for the requirements of law.
Like I said, there may be other things going on that neither of us is aware of; however, it appears clear to be that some members of the faithful there should appeal this directive to Ecclesia Dei.
However, this situation is completely differently than the FI situation.
Now, mind you, if Ecclesia Dei blows them off, then the claims of conspiracy by Rorate Cæli will start to hold a lot more water.
In the FFI situation, the Superior General who made the decision was removed under a cloud of false accusations which were later withdrawn. At this point, "traditionalist drift" appears to have been the major crime.
Like I said, there may be other things going on that neither of us is aware of
Difficult to conceive of any other things going on which would justify this action by the bishop.
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