AADHAAR and BANK ACCOUNT
Aadhaar Seeding/Linking with Bank Account
If Bank Account is Seeded/Linked to Aadhaar - it facilitates credit of various Govt. sponsored subsidy/benefit schemes such as DBT, MGNREGA directly in Bank accounts through Aadhaar Payment Bridge System (APBS).
Aadhaar Updation in Bank Account
If Aadhaar is updated in Bank Account - Aadhaar Number is updated only in Bank records and cannot be used for receiving credits of Govt. sponsored subsidy/benefit schemes.
Moral of the Story
You should Seed/Link Aadhaar to only One Bank Account where you want to receive Govt Subsidy/Benefit/Pension etc.
However - You may Update Aadhaar in all your Bank Accounts
(Above based on information recieved from my Bank)