Conflicting advice on statute barred debt

[bex6]

I received a letter today from the county court on behalf of Lowell / BW Legal. The issue date is 30/9/16 and it's for about £5k on credit card. I believed it was statute barred as the last time I paid was June 06, and the default notice was Sep 06... Lowell have had the debt since 24/6/14 and I believe have sent some letters (I'm not certain, I have MS - which is why I defaulted in the first place - and find it difficult to deal with paperwork). I called National Debtline and they said it's not statute barred as that only starts when they officially called the full debt in, which was 18th Oct 06. I then called CAB and they said it's not statute barred as Lowell wrote to me during the 6 year period. Yet every forum and webpage I've seen (including National Debtline and Citizens' Advice!) states the statute bar dates to the last time I paid or the last time I acknowledged the debt in writing... So which is it? Thanks for any help anyone can offer.