error 401, thanks for some useful observations.
However, beware a hazard in the last situation; braking feels sufficient with reverse, but when cancelled the brakes haven't been contributing very much on a slippery runway due antiskid / autobrake selection.
See the Boeing briefing on slippery runways -
http://www.vipa.asn.au/sites/default...%20runways.pdf
Slides 14-17 graphically illustrate the hazard with autobrake and reverse on low friction runways.
Pilots may 'think' - seat of the pants sensation - that deceleration is satisfactory, but in reality as the effect of reverse decreases with speed reduction, and particularly if reverse is cancelled, the brake contribution is low to nil; pilots suddenly sense that the aircraft 'accelerates'.
Also, and as in more recent posts, the braking performance achieved depends on both accurate reporting and matched performance data.
Airbus has provided new OLD/FOLD data, but Boeing is unknown. Thus if the Boeing 'slippery' category has not been matched to the new runway condition reports then the performance expect may not be achieved. (No slippery category in RCAM). What is Boeing definition of slippery ?
e.g. in the Airbus presentation
https://www.icao.int/Meetings/grf201...-%20Airbus.pdf from slide 16. If Boeing slippery is somewhere within 'wet', (like RCAM 6 changing to 5) then then the additional safety margin needs to be 20 - 40%, much higher that the minimum 15%.