If there is a network composed of access points with the same SSID (such as a business or large house with multiple APs). Does windows phone automatically switch to the strongest signal without dropping connections? Or does it hold on to the current connection as long as possible despite there being a better connection available?
The phone (and any other Wi-Fi device) won't differentiate between two access points announcing the same SSID. Given there isn't a concept of a persistent connection (so, even if you were streaming media, you're just sending many smaller packets of data, that can be routed however the network needs to). As such it makes this virtually impossible to test, but I don't notice any break in connection when walking from one end of our site to the other, even though I know on the route, I pass five different access points.
Yes it sticks to the already connected wi-fi irrespective of better strength known connections available. It won't switch on its own until that network goes out of range. But if you turn off the w-fi and switch on again, it will connect to the strongest wi-fi available