The biz blamed its decline in Blighty on the "operational challenges following a billing system migration".
I blame it on their generally crap customer service. They are a very frustrating company to contact and when you do contact them the 'help' you receive is often pointless or wrong. I resorted to calling them last year because I was sick and tired of getting spam SMS from them advertising their 'black tuesday' deals or some such drivel. Took over half an hour to get through. Then the bozo I spoke to said it was because I didn't have children's number blocking on my phone.
When their Sure Signal service fell over earlier this year it took them a week to fix it during which people who called support were advised to reboot the device, reconfigure their firewall and contact their ISP. Those who chose to visit the support forum also got that advice but at least they could see the large thread at the top and if they read it finally realised it was a Vodafone fault and nothing to do with the customer or their equipment.
I need the SS3 as the only currently viable alternative to decent coverage (not that South Northants is particularly rural, especially in the largest town) so I'm stuck with these monkeys. But lordy what a shower they are.