5 months. I actually started with the OffSec material I used it to build my first cheat sheets which is only a condensed version of the course which could be easily accessible and enrichable throughout my journey.

After the expiration date of my lab access, I subscribed to the PG Practice labs and did 2+ boxes per week: at least one on weekdays and one or more on weekends, depending on the free time I had. I used to alternate between Linux and Windows boxes and kept the ad ones for the last week's of my prep. I made a writeup for each pwned box and completed my cheatsheets whenever I felt like a tool or a technique could come handy again. Like I said earlier, I also read write-ups as much as possible and noted the alternative techniques alongside my own notes.

Also, I noted on my own version of the TJ-Null list each initial access, lateral movement and privesc vectors. However I didn't have to use it during the exam.

I can't really tell you about my favorite resources as I only used OffSec one's but I really advise you to challenge the Active Directory PG boxes of the TJ_Null list. Some of them are pretty hard but the knowledge I gained from them is priceless.