Hi ClassicChris,
The closure of Testing Facilities around the world was initially due to the Covid-19 outbreak, so the reopening (and potentially any future re-closing) will likely also be in response to the current spread of the Covid-19 virus. Since you were not able to find any upcoming GMAT appointments at any local testing facilities, were you able to confirm that the Facilities were actually OPEN and administering the GMAT? I ask because there's a big difference between "all of the appointment spots have been filled" and "the Centers are not open, so there are no appointments currently available."
In terms of the broader issues that Applicants are facing right now, it's likely that most (if not all) of the Schools that you are interested in are already making plans to adjust their respective application deadlines. Thus, while you might not be able to make a Round 1 deadline in September, that deadline might be pushed back - and even if you can't make any Round 1 deadline, you likely have a reasonably strong chance at making a Round 2 or Round 3 deadline.
Before I can offer you any additional advice for your studies, it would help if you could provide a bit more information on how you've been studying and your goals:
Studies:
1) On what date did you take the At-home GMAT and how did you score (including the Quant and Verbal Scaled Scores)?
2) How long have you studied in total? How many hours do you typically study each week?
3) What study materials have you used so far?
4) On what dates did you take EACH of your CATs/mocks and how did you score on EACH (including the Quant and Verbal Scaled Scores for EACH)?
Goals:
5) What is your overall goal score?
6) What Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich