Momentum flap will bring average CoP closer to CoM but CoP will shift as JWST is rotated to point at different targets. Unwanted torque can be minimised by carefully choosing observations targets so it mostly cancels out but it cannot be done perfectly.
> As an additional challenge, the JWST observation schedule in the next 21-day period will not be known at the time of SK [station keeping] maneuver planning. A planned observation schedule one week ahead will be available, but the actual observation schedule will be event-driven. If a ‘target of opportunity’ arises then the schedule can be changed within 48 hours to point at the new target.
