Come on, they are liberating Poland.

But let's play out this scenario. So the Red Army is checked at the German-Polish border... part of the German army crosses the said border due to military necessities (pursuit, encircle whatever the retreating Soviets).
1.) will the Entente send a strongly worded telegram to Berlin that they have to immediately withdraw to the agreed border?
If yes: the Red Army recovers at some point and establish the Polish SSR... would the Entente allow it
If not: the Reichswehr is in full pursuit mode and they try to conscript a Polish Liberation Army
2.) will the Entete stop it? Are they sending their own troops to relieve the Germans at that point.
The pro-German Polish Anticommunist Army has cleared Poland while Germany and Poland negotiated an armistice/peace with Soviet-Russia.
3.) what cards do the Entente possess at this stage? Are they restart a war for a regime change in Poland? Who will lead the pro-Entente Polish Government?