Purchasing Multiple Google Drive Subscriptions, Possible?

Hi All,

If I have active yearly google one subscription for 2TB which expires in 11 months time AND I purchase another yearly google one 2TB subscription on the same account, will it extend my subscription expiry to further 12 months or it will just extend it by 1 month?

Curious to know as google 2TB yearly subscription is very cheap at the moment (via turkey).