Question

Suppose tonight is a full moon. What phase will the moon be in about 8 weeks

Answer 1

The cycle of phases has an average period of 29.53... days (rounded).

If the moon is full tonight, then it will be full again in 59.06 days.

59.06 days is 8 weeks and 3.06 days.

Does that fit what you mean by "about" 8 weeks ?