This request is to be able to set a custom add-on colour that would override the set service colour when a registered client has chosen an add-on.

For example, a service has two add-ons, one for the trainer bringing a demo dog and another to add a bath. If the booking is the standard colour no add-on has been chosen. If the booking is colour B then the demo dog add-on has been chosen, colour C means the bath add-on has been chosen. Users can then simply reference the colour on the calendar to know if something extra is required.