taxpayer applied 2018 tax refund to 2019 estimated payment

[BEA1]

taxpayer applied 2018 tax refund to 2019 estimated payment what bank account will stimulus check be deposited or will a check be sent. What are the procedures for this client?

[Just-Lisa-Now-]

Applying a refund to the next year doesn't submit any banking information to IRS. 

They will either see a check, or they can provide their direct deposit info to IRS later this week when that portal they are building for this purpose finally goes live.