On several occasions I have down loaded the charts in the AIP. When planning the trip they are in the memory. After shutting down the iPad and restarting for the trip the AIP charts have disappeared. Have I some incorrect settings?

I leave SD in "Live Data when Planning" mode all the time. I understand this also means "use stored data when flying".
In flying mode it should have no reason to try to get live data it can't obtain.
In the case of missing plates I think it would be better to have SD  say "the plate have not been downloaded" instead of "need connection".

Anyway, the original problem is intermittent, I currently don't know how to reproduce it.

Most of the time it works as expected.

I also just noticed in the swiss vfr guide that a few plates were still white in the list, even after a fresh "update all".
By selecting these in the list they were downloaded and then turned green

I've changed mine to live data when planning instead of the planning and flying option. I hope this makes a difference but the last time it did this I was on the ground not in flying mode it was just I had no Internet coverage so not sure this is going to change it in them circs but it might in mid flight.

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