Do all pilots know what to do when they hear "Delay not determined"?
Probably:
Hold until either
a) delay becomes determined, or
b) fuel runs down to minimums & diversion is necessary
In the event of RTF failure,
a) how would the pilots know whether the delay was determined or not?
So following standard RT fail procedures and hence receiving a red flare/light on final if landing really not possible, then diversion is probably the most sensible option.
b) if they did know (ie RT fail occurs after information passed) then diversion would be prudent.
The 7 minutes, after squawking 7600, before changing level (3 minutes before resuming flt planned route if on vectors) is so
a) you folks can get everything else (with working radios) out of the way, and
b) we have time to dig out the relevant Flight Information Supplement and look up the what the hell we're supposed to do next (see above)
Is there a particular scenario not covered here that you're concerned about, Neptune, or has something happened recently that we should (ie would like to) know about?
GL