enough. And Kevlar is a rotten "outside" cloth because it has little compression strength and fuzzes when abraded.
Spider cracks notwithstanding, I doubt that the damage has gone deep enough. UV may have made the outside poly layer brittle, but the inside layer should be OK.
So, I'd just paddle it until it breaks. Just don't take it on any wilderness expeditions or use it on whitewater. It's not really much good for those purposes anyway.
Kayak & Canoe Covers
2-3 Canoe/Kayak Trailer