Paying too much pension levy

Hi,
My query is as follows. I am a substitute secondary teacher and paid on a pro-rata basis, only being paid for the hours I work. This pay contains a certain percentage of holiday pay for the summer, Easter, Christmas and 2 midterms in the year that I do not work when the schools are closed. As far as I am aware pension levies thresholds are divided in 12 and applied to the gross amount earned each month, similar to the tax credits. The issue I have is that, as my wages are higher due to the included holiday pay and I am paying the majority of my pension contributions at the 10% rate. As I am not on a fixed term contract I may not have work from September to Christmas and possibly earn only around EUR20K for the year. In this case I should not pay any of my pension contributions at the 10% rate. I am wondering will I be able claim a refund of any pension contribution overpayments? Can it be done in a similar way to a tax refund?
Is this an issue for anyone else??
All contributions welcome.

Yes, you can apply for a refund at the end of the year.
I work a shift that results in different amounts of pay every week. On one week in particular, I pay the higher contribution but have been told by my employer that I will be able to get the excess refunded at year end. We’ll have to wait until then to see how it works.

Thanks Jim, thats good news, hopefully it'll be easy to reclaim back.