Random EEPROM write/put failures - ARGON/XENON

So this is interesting .... sometimes it just stops in the Creating table function.

If I uncomment the //Check what we write section, then it takes much, much longer to lock up, which is why o wanted to use the retained iterationCounter - but that is not behaving as I expect see:

I have left the Argon off for 4 hours now and just connected it and so far has done 150 iterations all ok .. so I will let it run overnight and see what I get?