New bulletin issued has instructions on replacing compressor's delivery valve, air drier and relay (plus performing a control module software update) when amber or red suspensions warning light turns on and "Suspension system inactive' displays in the message center, or should there be a marked degradation of suspension system performance along with the fault messages and/or warning lights. Several DTCs may also be stored in the related control module. Current part #'s for delivery valve, drier and relay kits are included in the bulletin. As always, check the VIN range and, whenever possible, the stored diag trouble codes before assuming this fix applies to you... Note for example that MY2011 RRS are not included in the TSB.
Also posting workshop manual's sections for air compressor + drier removal and installation, for experienced DIYers / indy shops or those of us without a factory warranty and willing to give these procedures a shot on our own (you'd still need someone with up-to-date diagnostics to update the control module software per TSB, though.)