Flight Crew Air Transport Pilot (ATP)
Confusion; Situational Awareness; Workload
ATC Issue All Types; Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Undershoot; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Requested ATC Assistance / Clarification
Procedure; Human Factors
ATC assigned a new altitude crossing restriction at MAYOS intersection on the IVANE5 RNAV arrival of FL220 instead of the published between FL260 and FL240. At the same time they slowed us to 250 KIAS instead of the published 280. This was done very late and we were unable to both slow and descend. We were flying an [a heavier A320 series aircraft] at a high landing weight and it was not physically possible to make the new restriction. We asked for and got the restriction deleted and we did a 'best possible descend and slow'. There were no conflicts or issues in this instance.ATC has made it a habit to change the crossing restriction at MAYOS. I am told it is a 'turf war' between Washington and Atlanta Centers. However; I have never flown the IVANE arrival as published. One thing that is always changed is the crossing restriction at MAYOS is changed to FL220 from between FL260 and FL240. This alone is a problem as we as pilots have to wait for ATC to give us the change for us to put it into our FMGC and then allow the aircraft to recompute or we have to override the automation and hand fly.In addition; we were given this clearance late and they compounded the issue by having us slow below the normal published descent crossing speed. All of this became impossible to accomplish as a [heavier A320 series] at high landing weights just will not slow down and come down that fast. We were forced to tell ATC that we could not comply with the newly assigned restrictions.ATC has been issuing a crossing restriction at MAYOS that is different than what is published. They must figure out what they want at MAYOS and publish it that so we can properly fly this arrival. This is a 'minor' problem; but it is happening every day and will eventually cause a 'major' problem if not fixed. We need to have the arrival published with a reasonable expectation that we will fly it as published. Right now that is not happening and ATC must be forced to fix this issue.
Pilot reported of being assigned a new altitude crossing restriction instead of the published restriction. Pilot was also told to slow 30 knots more than the published speed. Pilot advised they could not slow down and get down and asked for and received relief on the crossing restriction.