This sounds like the best approach.Pretty much.
They do 1 hour and 4 hour slots, complain to Sainsburys and they will just have the driver switch up his route slightly, he will still turn up before 8 but hey if it means that much to the op.
Telling your neighbour what they can and can't do after being in the place for 4 weeks would be a right laugh to watch though, so if you do try and get it on video.
Make sure you sign off as Karen.