Today's Teslarati article SpaceX wants to offer Starlink internet to consumers after just six launches talks about the new website https://www.starlink.com/ shows several images from it, and tries to describe some of the bits on the Starlink spaceraft itself.
Caption for full image, shown is a cropped section.
Starlink’s star trackers (left; used for precise pointing and positioning) and what are likely four gyros, also used for pointing and orientation. (SpaceX)
I don't think the satellites have cold gas thrusters, but there is one Hall effect ion thruster for orbital maneuvers (e.g. raising, lowering, phasing, station-keeping).
Question: What are the strategies that are available to the Starlink satellites for momentum-unloading of the control gyros?