I have used several low-cost carriers in Europe on a bunch of flights on various trips and I've not had any problems. This is the first schedule change I've had, and as you can see it was resolved (so far). One thing I always try to do is build in enough time for delays or cancellations and make sure I have an alternate plan if the flight fails, although that's never happened yet. And it's not just low-cost carriers that can make plans go sideways - any number of problems can occur with any method of transport.