7th year with trailer tires, is it time to change them?

If you plan on some long trips, I think going on 7 yr tires is a risk that most would not be comfortable with. I do think many things enter in, such as stored out of sunlight, parked on a good surface for extended tire life, is there a good margin of max tire wt, compared to trailer loaded wt. You know how they were used and stored, so you need to decide the risk factor.

Jerry