Folk are entitled annual leave equal to to 5.6 times the number of days in their normal working week up to a maximum of twenty-eight days.
Employers can add bank holidays to or include them in that entitlement. They can also determine when employees can take their annual leave.
The break of twenty minutes applies after working six hours the employee can take that break away from their workstation.
Where do the folk who don't work on reception take their break? Why can you not go to that same place?
It would be worth 'phoning ACAS for advice,
https://www.acas.org.uk