How do you guys go when the 2nm drops to 1 nm during the intermediate phase for Eg then to 0.3 for final? I guess by then it's the fore & aft separation that's important.
If you notify RNP2 as your standard you are signifying you are purely an enroute user. If you are doing an RNAV appch, then you will be notifying RNP APCH (S1 or S2 w/baro aiding). The GNSS doesn't drop to the 0.3nm RAIM limit unless an RNAV approach is activated.
Even if you are in Terminal mode, you would expect that ATC are aware of your departure and destination. If your RAIM limit is exceeded, you just notify as per AIP ENR 1.1 Section 21.3 and a different based separation standard (ie. non GNSS) will be applied.
Maybe the Ranga could confirm?