I would be happy to help you with Polish leg. EPBC is most obvious choice, but that not so good for socializing, meet-ups, etc.
Peter, it depends on your timing. Note, that 2018 is 100th anniversary of Polish aviation, so there is a lot of events in June-August, you may join each weekend on many A/Ds. But anyway, EPBC is always good if you want to drop in for couple of hours, refuel, etc. – open 6-22, lights (no instrument), long concrete, etc.
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