Glad to hear wifi calling is working for you.. wifi calling shouldnt be having any affect on your broadband speed.
However, in regards to your other comments..
As you may know there are many reason why you get the broadband speed you do.. It could be the cabinet you are on is suffering congestions or its full, most of the time its the indirect distance a line runs to a property. It could be down to the quality of the line, or it could be down to internal wires and extensions. The people further away, could be connected to an alternative cabinet, have a new line to their home with errors, they may have a not have as many extensions or their hub maybe newer..
To check the speed and connection..
On the home hub (192.168.1.254), advanced settings, Technical Log- then log in..
On the information tab you will see a few things but look at the Maximum data Rate (this is the maximum your line can support from the cabinet). The data rate is the sync rate of your hub, and finally Latency type...
Also do a broadband and perfomance test from the home hub page, this will check the speed to your connection, it will also check your line. Check it against what BT say your speeds should be around Broadband Checker if you feel your speeds are under what they should be contact BT Broadband Faults.
Virgin on the box seems, but as ex virgin customer make sure you are aware of their Broadband Traffic Policy that runs from 6pm-11pm daily
Thanks for posting your comments..
The coverage map is a guide rather than an exact science so it can be often hit and miss and you wont be able to ecver really tell how good coverage will be until you have a sim. The Coverage map is unable to take into account what a structure is made from so that can often lead to dissapointment. As BT Mobile is an MVNO it runs on the back of EE's network so additional cell locations is down to them in most instances. All networks unfortunatly have black spots when it comes to coverage, and getting new mast put up can be sometimes tricky due to planning in the area. Non of this helps you, but it seems your experience with the contact centre was not a great experience and feedback on the forums does get passed back to the relevant teams.
BT Mobile offer a 30 day money back policy, so I would advise people to cancel as soon as possible if coverage doesnt live up to expectations going past this point could show that you were happy with the service level when you joined.
Normally if you are in mid contract and wish to leave early, you would be expected to pay part of the monthly charge.
Im afraid nothing much can be done when a customer has poor coverage other than recommend wifi calling when you have access to a wifi network unless a new mast is planned, but If you are still have problems trying to cancel or would like to know what charges would be involved, I can ask a moderator to pop and have a chat with you..