A Level 4 candidate should be able to pass a R/T licence test in my view.
Thats my point, anyone who is capable of a pass in the RTF Test is at least level 4, but the examiner cannot award it, only a level 6.
From Art 37 of the ITU Radio Regulations:
37.1 The service of every aircraft station and every aircraft earth station shall be
controlled by an operator holding a certificate issued or recognized by the government to which the
station is subject.
37.4 4) Nevertheless, in the service of aircraft stations and aircraft earth stations
operating radiotelephony solely on frequencies above 30 MHz, each government shall decide for
itself whether a certificate is necessary and, if so, shall define the conditions for obtaining it.
37.30 2) For aircraft radiotelephone stations and aircraft earth stations operating on
frequencies allocated exclusively to the aeronautical mobile service or the aeronautical mobilesatellite
service, each administration may itself fix the conditions for obtaining a radiotelephone
operator’s restricted certificate, provided that the operation of the transmitter requires only the use
of simple external switching devices.
37.31 A radiotelephone operator’s certificate shall show whether it is a general
certificate or a restricted certificate and, in the latter case, if it has been issued in conformity with
the provisions of No. 37.30.
There are still people operating with National licences in the old format with stand alone FRTOLs and they do expire. To get it back, the priority is ELP not proficiency in operating the radio.
37.19 2) Administrations should take whatever steps they consider necessary to
ensure the continued proficiency of operators after prolonged absences from operational duties.