Bad Wi-Fi performance after last update

[Danp]

Not sure if I'm alone here but since the last update Wi-Fi range and stability has taken a huge hit since the last update. I initially thought it was a problem with my own router but have since tried two other Wi-Fi networks and find I have to sit within about 2 metres of it else I have big problems with connection and it dropping out.
Anyone else having this problem?

[TimmyTooMany]

Hi, I too am having trouble. I have an HP laptop, a Sony Xperia 4 phone and the Xperia 4 tablet. The phone runs Android 5.1.1, the tablet Android 5.0.2. All are connected to a mobile wifi router. The laptop and the phone are rock steady, but the tablet is not. I am constantly getting the exclamation mark next to the wifi symbol. I try to connect to the router app with the tablet, and it says i am disconnected. I switch off and on the wifi on the tablet, it works for a few minutes (I can connect to the router on the app), then drops out again. Very annoying Sony!