He could have gone anytime over the past two days (and almost did,) but he waited until this morning. I sent Deb in my place, because she hadn't been in since Monday and because I was very unpleasantly hit with a cold last night. She was with him - had just said "Hello" and held his hand, and he went.
Which means I am right - I told her to go in because he was waiting for her!
His suffering is over.
Rachel and Justin have both heard the news, and are sad, but handling it well.
I'll post a proper update later, as I expect we'll be making arrangements today, and I want to get all that in place before announcing details.
Thank you all for your comments, love, and support.