You can connect your Dot to any number of networks as Jeff29 stated only one network will be remembered per dot.
I've had one dot connected to my home network then took it to the cottage. On Powering it up again I had to reconfigure it to the router there.
You can have multi dots at different locations all connecting to the same Account.
I have 2 dots a the cottage one is on its own account the other is on the Account with my Home dots.