Erdogan has been very busy for several years establishing refugee camps he uses as political/revenue leverage on other members of Nato countries to keep the refugees in Turkey or he'll cut them loose to further invade Europe...he's played that card several times over the course of the war to line his pockets....... When/IF these refugees return to Syria he's lost his leverage and cash flow from Europe and the UN...
He's going after the Kurds beyond the established miles of the safe zone now becuase He planned this once he forced his way into the coalition with empty promises he would not go into Syria....and everyone of the parties operating in the Syrian war knew this would very likely happen....which he why he wasn't invited to begin with. Erdogan is playing everyone now.....and has been all along. He has not lost his vision of being the Great Sultan of the Middle East.....He covets Syria as no other outside perhaps Iran.
Turkey is screwed in this sense. Most refugees are fake Syrians just like in case of Europe, some from Africa and Afghanistan are making about 5% or more of Turkish population by now. They are roaming the cities in great numbers, begging at every street corner, occupy vacant buildings, steal, rape and to other stuff they are known for.