Plot thickens. Capt Pit Bull, point taken.
"Do Not Descend RA" is also described as "weakening" and "corrective" on pg. 33, albeit in a different circumstances.
- During an RA, if [...] response to a Positive RA has provided ALIM feet of vertical separation prior to CPA [...] the initial RA will be weakened to [...] Do Not Climb RA (after an initial Descend RA). This is done to minimize the displacement from the TCAS aircraft’s original altitude.
- after ALIM feet of separation has been achieved, the resulting Do Not Descend [...] RA is designated as corrective. [...] In Version 7.1, the RA is annunciated as “Level Off, Level Off.
Interestingly, both of are entirely appropriate to the edge-case discussed.
+ There was a hard corrective RA so it is a weakening change.
+ To minimize altitude loss is exactly why the downgrade of RA happens
+ Preceding manoeuvre was corrective, demanding action.
Unlike the "preventive" RAs where passive monitoring is the plan - "preventive RAs do not require a change in vertical speed." (pg 30)
- Not modifying the V/S instilled by the previous RA is would clearly the wrong choice here.
IMHO technical possibility exists that passing 1100 ft some internal element nulls the ALIM value which would cascade the described desirable behaviour.
As well, the call "level-off" has the appropriate good advice once 40 seconds from ground contact. Unlike "monitor V/S" which might fixate the pilot on keeping the needle steady and/or observing where the red arc is - instead of watching the altimeter!
Admittedly, the document we have does not provide any guidance in this direction.