My guess is that there will be some major "new light" concerning the memorial, partaking, anointed, etc.
EOHB: It would be easy, just declare the "12 Tribes of Israel" in Mat. 19:18 and Rev. 7:4-9, - that are now pegged at the "Earthly Hope" -, to be The Israel of God, aka Spiritual Israel. Then all the 12 tribes would be in the New Covenant, and voila, all partaker! but that would be too simple.