No. When you enroll in your new Medicare drug plan, you will need to make a new choice about how to pay your premiums. You can again choose automatic premium deduction from your Social Security benefit. Premium deductions generally
start two months after your drug plan submits the request. This means that the first time the premiums are withheld from your Social Security benefit,
two monthly premium payments will be withheld. After the first time, only one monthly premium payment will be withheld from your monthly Social Security benefit.
(Source: U.S. Department of Health & Human Services)
Also see:
Why am I not allowed to have my Medicare Part D premiums automatically deducted from my monthly Social Security check?