Can I add my two pennyworth to the discussion on Hex 346494.
I saw a C295 on approach to Lanzarote on the 25 Feb at he same time the hex appeared on my box at what I thought was the appropriate height. On the 28 Feb I saw a C295 flying low level, say 200 feet, but did not pick up any Hex. Today I again picked up the Hex but this time did not see anything as I was not looking!
Maybe a Piper was also around at the same time but the only light I have seen is EC-NNX this morning.
Don't know if this helps or muddies the water even more
Jim