ACLS65;
Previously I think the options discussed were either a climb or dive greater than 1800fps, or possibly some sort of cabin depressurization.
Let's be clear about this piece of information as well. It is the cabin-rate-of-climb (or descent) that is being referenced here and not the aircraft rate of climb or descent.
The concept is perhaps not as easy to understand as one might expect - while the aircraft is climbing to cruise altitude, say, FL350, at a rate which is typically between 1500fpm and 2500fpm depending upon a lot of factors, the cabin is being pressurized such that it's pressure is equivalent to that found at between 6000 and 8000ft, approximately.
Briefly, air taken in by the engines is partially diverted (at the second and third stages of compression in the engine), through an air-conditioning "pack" into the cabin. The outflow valves in the aft fuselage close so that the air escaping the cabin through these valves is slightly less than the air being routed into the cabin through the air conditioning packs, thus pressurizing the cabin. The cabin "climbs" from it's starting pressure which is that of the departure airport, to a pressure that is equivalent to an altitude described above. Cabin "altitude" is stated in hundreds of feet, such as, "the cabin altitude is 7600ft". That means the passengers are breathing air (not oxygen, as many think) as if they were at 7600ft, or just a bit higher than Denver, Colorado or walking up the road to Machu Pichu, etc.
The "cabin-rate-of-climb" is thus the rate of pressurization from it's starting altitude to it's cruising altitude. Typically, if one departs near sea level, the cabin rate of climb is around 300 to 500fpm, controlled by the Cabin Pressure Controller(s). Part of the input to these computers would be the static pressured outside the aircraft so the CPC "knows" how high the aircraft is.
Now it makes sense to talk about a "cabin rate of climb/descent" and one can readily see now why a cabin rate of climb of "1800fpm" up or down, is not only excessive, it is an indication that the CPC is not able to control cabin pressure, for whatever reason.
Hyperveloce and others will now understand why a cabin rate of climb has nothing whatsoever to do with, nor is it an indicator of, an aircraft "stall" condition. It is an indication that not all is well with the CPC, the outflow valves, the cabin itself or...?
One can also now understand what a pilot means when a pilot says "we caught the cabin" - it means that the aircraft altitude is the same as the cabin, usually in descent, and to keep up, the cabin begins to follow the aircraft rate of descent.
Obviously if one thinks about it, there is a cabin climb schedule which matches the aircraft rate of climb so that "catching the cabin" does not occur. In climb this rarely if ever, happens but if one is descending very quickly, one can get to the altitude that the cabin is at and then the cabin will descend with the aircraft - very hard on the ears.
The ACARS advisory message, (see the earlier description of same) advises the crew of this rate of climb/descent. The cabin pressure warning (red master warning, steady chime, red ECAM message "CAB PRESS") do not occur until a cabin altitude of just under 14,000ft.
We cannot know the full meaning, (ie, was this a depressurization, a CPC fault or...?) of the advisory but we do know that at some point the fuselage/cabin structure was compromised/breaking up, at some point between 350 and sea level.