First, decide if this is the option you really want. In the Request for Updates template, a list the service preferences the volunteer has already chosen appears. You could add a sentence to this template to remind volunteers if they CANNOT make those times this year, to update and remove that preference.
To remove all holiday service preferences from last year so that volunteers could select them again if they wanted, but not be automatically scheduled based on last years preferences:
- Delete the yearly services in the Service Times pane
- Create new yearly services that look identical (Digitally it will be a different service, even though visually it looks the same, thus removing it from all volunteer profiles)
- Processed as normal, reminding volunteers they can add the yearly services to their preferences