Xbox Live Account Question?

Ok, mistakenly I thought I upgraded my preexisting xbox 360 account (with all the gamescore and acheivements) to xbox live, but it turned out it created an account with 0G but the same gametag! So, I upgraded this to a 12 year Gold subscription, but now I'm reading I could have linked my preexisting account with all the gamerscore and acheivements to xbox live in the first place! Is there anyway I can transfer the 12 month gold subscription from my 0G account to the other account with all the gamerscore and acheivements?