TBM 960 pilot reported static system instrumentation providing erroneous flags and error messages due to frozen water in the static system. Pilot diverted and landed uneventfully.

Narrative

During level off at FL280; Crew Alert System (CAS) Message 'Full Authority Digital Electronic Control (FADEC) FAULT' annunciated. Associated was actioned and completed; followed imediately by Airspeed and Altitude mismatch flags displayed on both PFDs. The AIRSPEED UNRELIABLE was actioned; including actuation of the alternate static selector.Altitude and airspeed indications on the LH and RH Primary Flight Displays (PFD) fluctuated eratically; alternately indicating a climb and descent; increasing and decreasing airspeeds. Electronic stability systems; engine protection systems; and Transponder equipment inputs received erroneous data which included aircraft altitude.ATC reported an indication of the aircraft in a descent. The standby instrument; utilizing the alternate static source; indicated level flight at FL280. A descent to FL240 was requested and granted by ATC. Prior to reaching FL240; further descent to 14;000 was requested and approved. Descending below FL180; IFR was cancelled and acknowledged by ATC.Upon reaching 14;000 (OAT 1c); all error flags and CAS messages were removed and altitude; airspeed; and engine indications returned to normal. Two SATPHONE conversations with the Service Center avionics personnel were conducted in an attempt to confirm the suspected cause of the fault to be water frozen in the static lines. Due to normal aircraft and systems indications at lower altitude / warmer temperatures; the decision to remain at 14;000 and change destination to the Service center was made to enable inspection and repair as required.Upon arrival at ZZZ; the static lines were serviced with nitrogen and found to contain approximately 15 ml of water. The flight was concluded uneventfully with no adverse effect on aircraft or occupants. Erroneous indications of altitude deviation were due to static system blockage and resultant transponder input data error. No actual altitude deviation occurred.