I sat and passed the CCSP today. Got my CISSP 3 years ago, nearly 20 years in IT/InfoSec/Cyber, last 5 years as a security architect.
Finished the exam in 140mins, probably could've been done in 2 hrs but slowed down towards the end.
I only read the OSG 2nd edition, and initially did it's easy chapter questions over a number of weeks mostly weekends. Then watched a course on Cybrary just to re-review the content from someone else's perspective.
Did maybe 120 practice test questions from the official test book (using the online Wiley version of it) the night before...that's it.
Last 2-3 years have been undertaking a lot of client project work offering security advisory for projects that use a lot of cloud, mostly AWS, and in the past year also got my AWS CLF and SAA certs. So I've been exposed to a fair bit of the stuff CCSP covers in the real world.
I felt CCSP was easier in the sense there's less content to learn and understand/remember, but from an exam question perspective they're definitely written in that world-famous annoying (ISC)2 way to make you really have to look for things to eliminate possible answers. Some are very clever, some are just poorly written, no ignoring it.
The new exam comes into effect on Monday, and new materials come out later in the year, but I think the current would still get the job done. Perhaps either give yourself some time off and wait for those (as the exam will in time also change from linear to CAT), or just spend more time reading stuff like the OSG but also many of the CSA and NIST documents the book recommends to also study. Make notes as you go along etc.
Best of luck, you'll get there!