Originally Posted by Ultralight

If you called scheduling and asked them to put you through to the captain, you could tell him / her that you are on the airport shuttle bus on your way to the gate. If the captain had any sense he would call for boarding and get the ATIS, clearance, and have the FMS loaded up so you could depart as soon as you made it to the gate.

At my old company both flight attendants and at least one pilot had to be on board prior to passenger boarding. Not sure about SkyWest.