Existing Wording: Payer and clinical systems will likely eventually need to support Argonaut, STU3 and R4 versions of the specification.

Proposed Wording: Payer and clinical systems will eventually need to support Argonaut, STU3 and R4 versions of the specification.

Comment:

Remove the term "likely"

Summary:

The term "likely" seems like unneccessary wording, since it is followed by the term "eventually". Only "likely" or "eventually" should be used in this sentence. The latter is preferred.