Exactly, this sounds like such a grown-up way to wind down a working relationship! I'm sure you'll stay in touch with that person and perhaps even refer people in their direction in the future.
I've stayed in touch with people even with "short" notices (1 month in my case) even if my leaving was a surprise. It just means the managers were professionals and didn't make me miserable as I was leaving. In one case, my CTO was an absolute gem through my entire stint there. It falls as much on them for me to want to stay in touch