Flight Crew Air Transport Pilot (ATP)
Communication Breakdown; Confusion
Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented
Human Factors; Procedure
During descent prep; MEM ATIS was calling for landings on rwy 36L; 36R and 27.  We set the FMS up for ILS 27.  We were flying the BLUZZ ONE RNAV ARRIVAL.  We were instructed to abide by the altitude restrictions on the arrival.  We descended to 10000 feet prior to BLUZZ for altitude restriction at COPEN as depicted for landing rwy 27.  When handed off to MEM APPROACH we were told to expect rwy 36R; which changes the arrival altitude restrictions to 14000 feet at LTOWN.  We queried ATC about the altitude and they told us not to worry about it.  We were on course at all times.  The crew should of asked MEM Center what runway to expect.
Wrong arrival transition flown; resulting in descent to an incorrect altitude. Four thousand foot altitude deviation.Arrivals with descent 'windows' and multiple runway transitions may reduce ATC workload but can significantly increase flight crew workloads. As such; when landing multiple runways that trigger significantly different transitions off the same arrival; ATC should be required to state the appropriate RUNWAY transition; not just landing direction; e.g. 'descend via the BLUZZ1 arrival; Runway 36R transition'.
CRJ-900 flight crew reported deviating from charted altitude on arrival to MEM; citing confusion regarding runway assignment.