In one way yes; in another way, don't know.
The yes is that it post-cycle, as well as other times, it provides its usual benefit of increasing insulin sensitivity post-insulin cycle.
But as to whether besides adding an improvement (which it would also add relative to the normal state) it speeds the natural recovery of insulin sensitivity, I have absolutely no knowledge.
What I mean by that is this. Let's talk about rate of improvement as say X% per month, though it wouldn't have to be a fixed value. Metformin also just adds some amount. So does metformin, post insulin cycle, both add that amount and increase the rate X? That's what I'm saying I don't know. An analogy could be HCG, in cases where testicular function is good, say HCG was used in the last 4 weeks. HCG in PCT would provide its usual addition, but would not improve the rate X. I'm not saying metformin would work against, as HCG does, as I doubt it would work against, I just don't know if it would speed rate.
It can be worth taking. It's possible (found in a study) that testosterone level can be reduced which could be an issue for natural use but not of concern on a steroid cycle. However in practice it's worked very well for naturals so I'm not convinced on the testosterone question.
Usually 500 mg at a time with carb meals or some of them, but not more than usually 1500 or 2000 mg/day. Starting with lower dose such as 250 mg to assess tolerance is best.