With the introduction Level 70, has the group experience gap formula remained the same?

I guess what I am asking is: What is the lowest level a character can be to get group experience with a level 70?

This is just normal grouping. Not LDoN or Expeditions, etc.

If the formula remained the same then the lowest level a 70 can group with is 47.

Common sense is usually the best formula. ;)

~Firemynd