Scheduling for weekend = normal vs 24/7 work by same resources

I’m trying to schedule some technical activities, where some tasks have to be done during weekend.
Resources available works in “shifts” or better say flexible - if needed they work during the weekend with compensation to other working days or by overtimes
I would like to somehow mark the tasks which must be done during weekend (ie. outage of systems) while other tasks should be performed diring mormal working time. All tasks are realized by same resources.
Is there a way how to model this situation?
Thanks in advance

@JanM You may be able to set this up by setting the task up as a “Meeting” task and assigning a second resource to the task that is only available on the weekend (for example, you could create “System Downtime” resource that has no work hours that overlap with the project’s regular work week).