There is (I think) a rule about how long it takes you to travel if you're called into work.
Yes, it's doubtful if they would allow Warsaw because there's simply not the frequency of flights compared to runs to Amsterdam or Paris.
I would be grateful if someone could tell me more about it.
Your best bet is Ryanair or Wizzair. You could also try Enter Air, Small Planet Airlines and Smart Wings, but you might run into difficulties with the language issue there.
An outside bet could be to try Nordica, as they use English as a common language onboard.