Hi Fuji Abound,
If I were in a hold with an EFC time, ie. "Descend and maintain 3,000, enter the published NDB 5 Hold, Expect Further Clearance at 16", then I would continue holding until the further clearance was given, if it got to 16 minutes past the hour then I would question the controller who may have forgotten about me (yes it has happened a couple of flights before my flight test).
However if I had lost communication then I would cross the holding fix at time 16 to proceed outbound on the NDB 5 procedure.
A little tricky in that I haven't been cleared for the approach as such because they wanted me to hold. If whilst you're in the hold ATC would like you to continue, then they (ATC) would issue you with a procedure clearance. However when you've a radio failure, that goes by the wayside.
So in short, if you're in the hold or on the outbound etc and you have a radio failure they would expect you to commence the approach (ie, leave the holding fix at the EFC time) or if outbound simply continue the approach as if you had been cleared for it.
Best wishes,
Charlie Zulu.