Slight kick back on the starting handle

["Slack Alice" Simon]

I would retard the ignition until it doesn't kick back - or is just a little kick.   A big kick indicates too much advance.

Both my cars have manual advance, so it is easy to do, and easy to replicate the kick back situation just to get a feel for it.

But if you are sure it is running smoothly and not sounding over advanced then don't worry too much.