I contacted a potential advisor for a PhD program. He replied to me that he was not in a position to accept any PhD students at this time. But he also wrote to me:
"I'd also be happy to chat about the program and my work generally if helpful, but would realistically have to be in mid-January. Let me know if of interest."
I am not sure what and how should I reply to him. I am interested in having a talk with him, but what should I ask?