Can anyone help!

We are a smallish company with around 400 employees. The board has asked we look into the possibility of running a flexible holiday scheme as a starting point to launching a bigger flexible benefits scheme.

Through salary sacrifice we will allow people to buy or sell a maximum of 5 days holiday or whatever the weekly hours are a part timer works.

I am really stuck around the issue of what to do if someone purchases holiday (e.g. a full 5 days) at the beginning of the year but then drops down to say only 10 hours. Should you pro-rate the entitlement and make the necessary adjustments through the payroll or should you allow the individual to continue to have this holiday they have bought? My concern is if someone has bought a full five days (40 hours) and drops down to 10 hours they actually purchase 4 full weeks of holiday!

Any help, guidance or suggestions would be much appreciated.

Thanks

Brian

Brian Moore