Generally B&W are very well put together and can be dismantle very easily. Unless there is any burn out problem or driver damage you can easily open the front baffle and tighten the connection. Before doing that get the speaker's service manual.
B&W moved support (in India), from Audio Vision to Neoteric.
I logged a support ticket on B&W site and got a very prompt response from the team asking for further information.
The team is still putting together their stuff, its not yet publicly announced this service setup.
Will share with you contact info, as soon as I get details.