Unless they purchased a fare which allows changes (which I doubt, otherwise you wouldn’t be asking the question in the first instance), chances [to be moved to an earlier flight] are virtually next-to-nil I’m afraid. The Warsaw ‘shuttle’ services are normally very busy and mostly operated by smaller aircraft. That said, a limited delay arriving into Warsaw airport wouldn’t compromise the connection, I often see doors closing literally 2/3 minutes before the actual time of departure in order to await connecting passengers and it is not a rare occurrence at WAW to delay flights for that particular reason (if you follow the Kafeteria’s thread, you will have probably noticed several posts about the airline’s operational issues in terms of on-time performance, especially during peak months). I would say (and sorry for going slightly off-topic) that with the Malpensa service operating on time and the Gdańsk flight arriving say 15 minutes late, your relatives would still be able to make it.

I hope this helps and that indeed everything goes smoothly according to plan.

G