mcelroytutoring, it does say on the website that you can take online attempts within 16 days of in person attempts (I knew I had seen it before, but I actually just checked and after some searching I found it still there on one of the FAQ pages). I'll post the exact wording below.
But as you indicated, if the reason we are jumping from 2 online attempts to 5 online attempts is that the question pools are merging and that the online GMAT is now going to be just an at-home delivery of the same test you take at a test center, that will mean the end of this loophole. For now the wording below is the wording on the site, but I gotta believe that the online GMAT is no longer going to have a separate question pool and that this loophole is going to go bye bye.
It's not the most consequential thing in the world, but I have a couple of students who are gunning for R2 but who won't be ready to take their first try until early December. So without the loophole they may end up having the space to take the test only twice, but with the loophole they might be able to take it 4 times (2 in person and 2 online). Since I already mentioned to them that this might be possible, they are going to be disappointed if it turns out not to be so!!!
Here's the wording from mba.com:
Can I take the GMAT™ Online exam more than once?
All candidates will be allowed two (2) GMAT™ online exam attempts.*
Note: The GMAT™ online exam can be taken once every 16 calendar days. However, you may have a GMAT test center appointment within 16 calendar days of a GMAT™ online exam appointment.
*Beginning October 20, 2021, the number of times you can take the GMAT™ exam delivered online will increase. Online exam attempts will continue to count toward your overall GMAT™ exam attempt limits – 5 in a rolling 12-month period and 8 in a lifetime. You can take all of your exam attempts at a test center or online, or a combination of both – the choice is yours!