I upgraded my broadband last week (Monday 29th June) and it said that my new service would go live on the 3rd/4th July. However i have still not received my new router and i never received a notification about it being dispatched. But my account has been charged the 6.99, so i know it went through. When i look on my account online it still says that a change of service is in progress.
It sounds like your change over date has been pushed back by a lack of Openreach technician availability. This automatically delays the shipping of the hub but Plusnet have to manually advise you of the delay. This sometimes gets missed.