The Rebbe blesses that Mordechai Ze’ev be raised to Torah, chuppah, and good deeds, citing the Previous Rebbe on the significance of the upsherenish. In a note, he rules that etrogim in Australia may be used despite import restrictions, as the prohibition is on place, not on the fruit, and ownership remains intact.
https://www.torahrecordings.com/rebbe/004_igros_kodesh/elul/1189