I'm in the same boat as you -- quite disappointed with the online whiteboard requirement.
Fortunately, I have a GMAT score (albeit, a poor 640 Q44, V34, IR8, AWA6), but I really do not want them to consider that score for my application. Even though I sent them these scores, I did not report scores on the application and wrote in under additional information that I planned to retake it prior to the original deadline.
If I were you, I would plan on taking the online version (as will I), and then pray that testing centers open again before the deadline OR that they waive GMAT scores entirely

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As a deferred applicant without submitting GMAT scores, I wonder if we will still receive interview invites during the same time period from April 20 to May 14 or if it will be delayed until later.
In same exact boat - had a past GMAT, didn't submit it officially but explained it in my additional info and sent them scores. We'll see how everything pans out. Best of luck!