I was involved in the original fiasco of the same thing, there is a thread on here about it.
I pay £15pcm for the Red10 pack, my phone has been used in Turkey. Zenas phone is a 2nd line at £12.50 for the same tariff, her phone not yet used in Turkey as we changed over from EE in December last year. Also have home broadband, all payable with 1 DD on the same account.
I waited 2.5hrs on hold yesterday to get a definitive answer after receiving the email.
My options; for my phone I can choose a new tariff at £30pcm on a 24m contract, 1st 6 months discounted to £15.
Zenas phone not subject to the 6m discount so straight from £12.50 to £30.
No alteration to the broadband.
I can cancel my phone under the previous usage clause with no penalty. If I cancel Zenas I'll have to pay the remainder of the contract so another 20 months!
Proper messy situation & not worth the grief for 2w in Calis, I'll either pay the £6 per day when necessary or switch the phone off except for the camera then as soon as I can I'll move away from Vodafone.
Last option is to get new sims & broadband elsewhere, cancel the DD & let them take me to court. I'm no rebel but I doubt that they would do that & am probably willing to take the risk, going to mull it over for a few days...