I don't know what oils he has now. I just presume that they are from a valid bishop. I don't think Ambrose did a chrismal Mass for him.
Presumably Fr. Pfeiffer has valid holy oils now. After Easter 2021 he will probably use oils consecrated by himself. These will be doubtful. Now, he probably gives validly the sacrament of Extreme Unction. After Easter it will be doubtful, also for the priests associated with him.
Your first statement, above, says " Fr. Pfeiffer has holy oils now" and your second statement, atop, say you "don't know what holy oils he has now".
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How can you be sure the ones he has now are valid if you don't know what he has now?
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It is unlikely he has had valid holy oils for some time unless, again, he violated canon law which demands that old oils be disposed of and new ones received yearly. Ergo, his, Fr. Hewko's, and the priests with him have given illicit and possibly invalid sacraments.
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Why do you "presume [the ones he has now] are from a valid bishop" when he has no bishop superior and no good relationship with ANY 100% unquestionably valid bishop?
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William aka Ambrose Moran is not valid.
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We must assume Fr. Pfeiffer is not a valid bishop until he proves he is.