So it seems that there has been no change since Kosovo in '99, when we were ordered not to use mobile phones because the transition from mobile network to landline was in Serbia!
The bad guys do not have to worry about the encryption because all they need to get from the base station is the number in the UK or Germany that Tommy Atkins dialled and then they can call Mrs Atkins at their leisure.
It sucks having to rely on the very limited Paradigm calls home but mobiles are not secure.