You may download here a document written recently by Fr. Hugo Ruiz Vallejo, faithful son of Archbishop Lefebvre, in which he makes it clear that we must not attend Novus Ordo, Indult, Sedevacantist, or Neo-SSPX Masses. Furthermore, no canonical agreement with Rome can be had until Rome converts back to the Catholic Faith.
Oh, how I wish that the three “Resistance” bishops, and the new one to come, would be so clear in their teachings regarding Mass attendance. One of these bishops, consecrated by Archbishop Lefebvre’s own hands, even teaches that one may attend any of the above Masses if one feels attendance will bear fruit. What a shame!