Please read carefully and note that the test retake option has nothing to do with the
announcement of the physical whiteboard option starting on 6/11, which happened yesterday 6/4/20, and everything to do with the
introduction of that option, which is already referred to in the past tense on the GMAC website, but is of course still 6 days in the future (6/11/20).
In conclusion and in support of
bb, yes, you should still be able to register for the pre 6/11/20 GMAT, and then later take advantage of the test retake option with the physical whiteboard for an additional $200, unless GMAC tells us otherwise. I mean, how would this be fair to someone who happened to take the GMAT Online yesterday or today, or is registered to take it tomorrow--to not allow them a retake with a physical whiteboard like everyone else? Are we to expect everyone to always stay abreast of GMAC announcements, 24 hours a day, 7 days a week? Yes, it would be nice if GMAC were to answer this question explicitly, but if we wait for a more specific answer on the official website, then we might find that the window of opportunity has already closed.
Now, a slightly different issue that has been raised here: are you gaming the system by registering now for a pre-6/11 test, after the news has already been announced? Sure, but if GMAC will let you, then why not? Everyone else who has taken the GMAT Online has been given the same "2 for 1" opportunity, so why not you as well? It's risk-free other than the cost ($400) and the time––and the fact that you won't have a physical whiteboard on the first try, of course. : )