How long should you wait between realising you have another kintype? I already have 5 kintypes, and I’m really against the idea of having another one, although I’ve been having strong feelings for awhile now that I do have another one.

There’s no rule of thumb, really. It sounds like its something that’s on your mind so I think you should pursue it. Do some introspection and see if it is really another kintype, or a false ping. It could be kinfeels caused by similarity to one of your other kintypes, or it could be a hearrtype or synpath.