There has to be a need. Then the priest would speak to his bishop and if he gets the nod there then he would speak with the other bishop whose jurisdiction covers that area. I believe Rome gets involved and does the approval but only when the bishops approve themselves.
If the priest is a religious then I believe his superiors are also involved.
There has to be a need. Then the priest would speak to his bishop and if he gets the nod there then he would speak with the other bishop whose jurisdiction covers that area.
I believe that this would be up to the bishop who is accepting the priest.
One that I know of got with a Byzantine priest to learn how to celebrate the Divine Liturgy and then took at 6 month sabatical to attend classes at the Byzantine Seminary in Pittsburgh to learn the other services and brush up on his chanting.
There is no set curriculum for this as this is not the prefered thing. It is out of the ordinary.
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