Clarify DEFINE schedule for #1560 more

[aj-stein-nist]

Committer Notes

Woops, clarify DEFINE schedule for #1560 more.

@Compton-NIST had pointed this I think more than once, and in the rebase and cleanup for final review and merge I missed this bit. Hat tip to @DavidAllardyce for bringing it back to my attention.

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[DavidAllardyce]

👍

[iMichaela]

Thank you. The change is reflecting our plan.