I have just returned from a trip to Denmark where I was unable to use
my Vodafone (pay as you talk) to make calls. Texts worked fine. I
contacted Vodafone customer services and they told me (1) they have no
agreement with any Danish network, (2) that I would need to do a
manual network discovery to make sure I was connected to the correct
network (thus contradicting 1) then (3) they have no agreement with
Canada (thus suggesting they had not read my e-mail). I will be
making my views known.

My question to the experts here is that if I change to another network
and keep my number, will I be in the same position? Or is the network
identified by a method other than looking at the phone number?

Thanks
Scott