Send notification when deployment starts

You can already configure a Deploy notification that sends a notification when a depoyment has finished, although this text actually seems to suggest that it'll send a notification whenever the deployment starts, but that's incorrect:

I sometimes get confused when I don't get a notification when I start a deployment. I'm very used to that initial notification, because other services do this too (such as Netlify). Adding that initial notification would, in my opinion, be a very welcome addition!