The Summit Instrument Activity Schedule (SIAS) is the schedule that is used by summit crews to determine which instrument tasks needs doing, primarily for setting up the instruments for that night.
The other use for SIAS is to communicate the release of the instrument and the telescope. Prior to release, no one should remotely command the instrument as day crews may still be working in and around the instrument and moving mechanisms may be a safety issue. Observers should not even start the instrument software until after instrument release. SAs should also be cautious when interacting with the instrument prior to release. In some cases starting the software involves homing mechanisms, so don't assume that nothing is being moved unless you are very familiar with the instrument's startup script.
SAs can edit SIAS tasks and SIAS is also where you set up your communication preferences for receiving notifications (i.e. texts) when the instrument and telescope are released.