Pre-Stage multiple schedules not available with available sessions and during work hours trigger

An additional schedule is required for an evening class which runs 6pm to 9pm once a week. The default daily schedule uses available session with the during work hours trigger so it`s not possible to use multiple pre-stage schedules. There are 30 - 40 hosts required during the day schedule which normally runs 8:30 to 3pm before scaling in with medium aggressiveness. The evening class only requires 6 hosts so leaving the hosts running all day until 9pm is not cost effective. Manually clearing sessions and shutting down hosts is the only way to current achieve this requirement.