BDSolomon,
Sorry you got taken in by Microsoft's obtuse naming conventions.
As far as PREVIEW updates, these are just pre-releases of the coming month's ROLLUPs. There is no corresponding preview for the coming month's SECURITY ONLY updates.
This is just another example of Microsoft using their customers as un-paid beta testers rather than using some of the $20+ Billion they receive in quarterly revenue to invest in proper testing of code before release .... it's cheaper and easier to let their customers do the testing.
I understand that you needed the outlook fix that (at this point in time) could only be obtained by installing the PREVIEW releases .... but now be very careful because you could have picked up other bugs from the PREVIEW release you just installed (be sure to keep all critical data/files backed up). Watch sites like Woody Leonards to keep aware of any reported bugs found in the PREVIEW release.