So after updating the software on 20th June I haven't been able to connect to the home wifi.
I have connected to another network, a bank of all places. Now, Samsung tell me it's not the phone and I needed to get intouch with my IP as it was a lack of bandwidth.
I've done that and they're saying the Internet is fine. I've disconnected devices that don't need to be connected and still no joy.
If you can find it in setting you can reset your wifi and Bluetooth settings then delete what wifi and Bluetooth connections you have then connect to everything from start again.