Low season extension earlier this year and annual leave allowance

[lancashire]

I am on a 35 hour contract.
Earlier this year around feb/ march the low season was extended by 4 weeks In Which I had a week off.

35 hours where taken from my annual leave although the working week was 33 hours for me.

I believe I am owed the 2 hours but would like confirmation if possible , as my manger and hr just seem to pass the book.

Also the exact dates of the extension earlier this year would be helpful for others in my office to check if there leave is correct.

Thanks.