IMHO, once the polyurethane coating goes, that's the end. There's really no way to bring it back. PU coated nylon doesn't have a very long life. As mentioned, a silnylon (silicone impregnated nylon) tent would probably last longer. The silicone can be renewed, too, unlike the polyurethane.

As long as it remains waterproof, you can probably continue to use it as long as you can stand the smell and keep it clean. It may not be ideal….



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May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view--E. Abbey