We do not see any problem with offering a CD with the option to withdraw one time without a penalty, provided that it would not be an option until six days have passed since opening the account (which would ensure that it fits under the definition of “time deposit” under Regulation D, 12 CFR 204.2(c)).
It may be possible (but unlikely) that offering this option only to certain customers may have a discriminatory impact on individuals in a protected class. But, the bank can counter any discrimination concerns by documenting its business reasons for offering the product only to certain customers (for example, by documenting that it would be costly to offer the option to all customers). As stated in the interagency fair lending guidelines, a bank can justify a bank policy that has a discriminatory impact by demonstrating the “business necessity” for the policy. FFIEC Interagency Fair Lending Procedures, p. iv.