Just doing the usual oi/water check......

I'd rather say you have another few months, not 20k, as it'll be 6 years old and the rubber ain't going to be in the best condition, regardless of mileage.

Generally the belts dont actually snap as such but the teeth get ripped off. It happens due to oil contamination both helping them slip and rotting the rubber over time. I had one go at 15k miles on a pinto engine. I had another one (pinto) still going strong in an old transit van after 110k plus and it never got changed. They are like light bulbs... You never know. A good belt oem supplied (not a pattern one) correctly tensioned, and kept clean with no oil seal weeps etc may last a very long time where the opposite is also true. Then theres luck...

Well my Dad picked up that Skoda for my sister the other day - all the stamps in the book regular as clockwork, some moderately expensive bits have been replaced within the last year or two - does look to have been maintained regardless of cost (T reg 1.6 Felicia). But weirdly, no mention at all of a cambelt replacement in all its 130k miles. And, on very carefully leafing through the owner's handbook (Dad, not me), it doesn't appear to actually recommend that the cambelt be changed - mentions check, but not change. So it's in the local garage getting new cambelt, tensioners and water pump - all for £200, which doesn't seem too bad.