Question

Heather has lost 30 pounds and kept it off for 6 years. she is currently in the ________ stage of change in regard to weight loss.

Answer 1

I believe the answer is Termination stage of change in regard to weight loss.
During the termination stage, the transformation is already complete and is very unlikely that heather will revert back to her old habbit.
In behavioral change like this, average people achieved termination stage after making an effort for 24 months or more.