Alan
Do not ask me why, but FLARF- has previously been used on large aircraft eg FLARF-01502 the M4-VM-T Atlant seen and photographed at Zhukovsky and is an ex Geographical Survey aircraft (a bit like a Canberra type aircraft). It has also been used on IL14's, An2's and Let410's.
RF- is now used predominantly on Military and Government machines.
So far RF- seem (but not always) to have changed to 1AXXXX from 14XXXX and 1BXXXX from 15XXXX. In many cases aircraft with RF- regs are still pinging their ex RA- code and whether this is just down to them not being bothered or not I do not know. However so far I found that all 1AXXXX and 1BXXXX codes I have picked up have tied up to previously being 14XXXX and 15XXXX.
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