I have been using the GTMs, LTMs and APM here at my company for a year now. I mainly handle creating load balance sites, making gtms additions, wipe ips etc. I build out our APM from scratch with no help besides my own research. I have messed with the CLI and have a license for two lab versions.
Obviously, this is different for everyone, but about how long should I study for the 101 and then 201 exams? With spring coming up soon, I'd like to get some of these done.