Do 18 month contacts with Scottish power exist

I had a contract with Scottish power that was originally supposed to be only 12 month ,but shortly after ,saw in some forum site ;I thouth it was from the email newsletter here that Scottish were giving a extra 6 months if 1 simply asked over the phone ;I did & they did agree to another 6 mths, but I never kept the letter & dont have any email either.
Having searched the forums here & the previous newsletters ,I cant find it or even through google searches .
Anybody remember ,of it ? ?
Spoken to Scottish power & they say they never do 18month contracts.