compressed hours and holidays

[Cherrystone123]

I have just started a job and I work 4.5 days a week; 2 days with 12 hrs and the remaining 3 days between 4-6 hours. I do 40 hours a week and get 5.6 working weeks holiday. That's all fine.
I now wish to take one day off on one of the days when I work 4 hours and my employer has taken a full day off my holiday entitlement. This does not seem fair; please can I get some advice

The fair way would be for your holiday entitlement to be calculated in hours (so 40x5.6), and then the number of hours for each day's holiday deducted. Or just take all your holidays on the 12 hour days (at which point I'm sure your employer would realise their "mistake"!)

Agree with mumblebumble it should be worked out in hours, not days.