Its a great fix if you have multiple holes and the covering is past its best.
The last stuff I used was Acrypol, but most are very similar. Its an acrylic paint, reinforced with hairs to stop it cracking with movement. The 'Special formulation for application in the wet' is bumf-the resin used does that for all of em.
Any good builders merchant should stock it, but expect to pay well. The brand I used last is out of business now-typical for my trade, but I've used Acrypol before.
The
roofing superstore is doing 5kg for £25-thats a good price to me.