I re-read my post above and noticed it could be interpreted as totally negative. That was not my intention.
They do have a long lead time, and say so. My point is don't wait tooooo long before getting involved to 'check up on things'.
I don't know about everyone else, but at least with me their customer outreach is non-existent, so after a while you might want to 'reach out to them', so to speak
BobL.