To be quite honest, I wouldn't change school just yet, especially given how far away the next closest school is. If you change, it will be very embarrassing if you then want to change back.
Go back over the occasions when lessons have been cancelled. If 75% or more are weather-related, then you're about right. If as many as 50% are caused by instructor non-availability, aircraft non-availability or aircraft U/S, then you need to start making noises.
50 minutes per month is really not enough. IMHO, PPL students really need to fly once a week. Given the above rate, I am very surprised you've got to the circuit in only five hours, and that would concern me - I am nursing a slight suspicion that earlier lessons may have been skimped. Ex. 10 alone should be a good hour. It may be, of course, that you really are a natural - they're rare, but they happen. This ain't a problem you need to worry about, and I won't call your instructor(s) unprofessional without evidence.
From what I remember about my time in the Emerald Isle, weather had a lot to do with almost everything. The song says there are 40 shades of green. Personally, I'd have been happy with only 20 shades and 50% of the rain. In Belfast, they say if you can see Divis Hills it'll be raining soon. If you can't see them, it's already raining.
Enjoy your flying!