How long do lines last?

I do a lot of freestyle flying (wingovers, asymmetric spirals, and SATs) on a paramotor. I had my Ozone Speedster 2 inspected after about 160 hours, two trips into a lake, and countless dewy mornings. They said the fabric was fine but that with the extra weight of a motor I should be cautious about doing SATs because the lines were within spec, but weaker than new.

He didn't say not to SATS, just to be advised that my wing is aging and they might need to be replaced in 50 hours. I'm not sure what to make of this. If they do go, will it be gradual or will half the wing blow out at once? Would you still SAT it?