I got my OSEP on 20 august and I was also surprised to even get all flags in 6 hours with secrets.txt. In this blog, I will be sharing my experience, my preparation, and my review on the PEN-300 in general along with some tips to help you out for OSEP.
I'm not gonna dive deep into this section since you can see the details of the course here (link to it), but overall it's an advanced course that teaches AD pentesting in hardened environments while evading AV and other security solutions like AppLocker and PowerShell CLM, etc.
I didn't do no preparation besides the content of the course itself.
First of all, I know most ask how long does it take to finish all the contents? For me, it took 1 month and half from 08/07 to 14/08, and then I did 3 labs and scheduled my exam as I was confident in my skills. (I also had experience beforehand of AD since I had CRTO and did real internship missions on AD with Orange Cyberdefense - shoutout to Amine-El-Boukhari for letting me in his missions - and also had most of the evasion stuff mastered a little from my security research internship with Sekera - shoutout to Younes-Adrouai for his amazing feedback during difficulties - and Sektor7 courses.)
Overall, I knew most of the course content that way I had it easy going through it. There's no definite answer on how long it should take you. All that matters is perseverance and getting most of the course.
I can confidently say that all you need for the exam is the course content :)
Overall timeline is shown in this schema
So after finishing the course and was feeling like it's a common thing, it's repetitive, I scheduled my exam at 20/08 at 1AM after I had some checks verified.
Then I started my enum and got foothold after 20 minutes which was surprising for me, unlike my experience on OSCP which took me hours that felt like eternity.
After that, I pretty much wasn't blocked in the whole exam till a point on my flag 6 if I remember right, and it was a mistake I've been doing on my end. Bizarre, it took me an hour but I quickly managed to figure it out, got my flag and rested for 30min, went for fresh air and meditating. I had also a rush in adrenaline since I was doing so well in the exam and I was so eager to finish it, but I decided to be wise and took a rest before going into the final round.
Now that I was back from my 30min rest, I quickly reached flag 9 and then got secrets.txt as my 10th flag which surprisingly gets you all points and immediate pass.
All the info about secrets.txt will be in your rules of engagement in the exam and will be clear how and where to find it, so don't worry about it. It's not like you're gonna play cat and mouse to find it.
After finishing the exam, it was 7AM which means 6h was enough for me to get OSEP.
I took all the screenshots needed and didn't finish the exam till I did the report in case some screenshots were missing. Honed my report and ended the exam. After 1.5 days, I had a mail saying that I passed OSEP :)
The course is so in-depth and informative, especially on the evasion stuff which makes you capable of continuing research and adapt all skills learned to modern solutions.
I would say more advanced AD attacks should be included and they are doing a good job adding them now like ADCS and JIT JEA.
Overall, the course is 10/10 from me. No flaws for this one. Even if you're experienced, you'll get most of it which will lead to the tips below.
Treat anything as if it's new. Don't let your ego get on you for something you already knew. You will always get something new from something you already knew.
Don't be stressed. It's not a life or death matter. Sure, it's a lot of $$$ invested there, but take it easy.
Take a lot of rests even if you're doing well. Helps the mind stay fresh, healthy, and productive.
For evasion, please please please consult these GitHub repos below. They will be a great help in exercises, lab, and exam. You can literally breeze through defenses with them as they combine all skills learned in well-designed scripts. (Maybe even more advanced than the course). Also, don't be afraid to use code. You earned your skill, you understood everything and wrote everything. Finding a tool online that does the same as your tool does and more efficiently is more valuable than anything.
I didn't use any C2. Just ligolo-ng is fine, but you are free to use any non-commercial C2 you want.
Finally, don't underestimate the report. Give it some time since you don't wanna fail because of the report. It's gonna suck, right? :)
Have fun and good luck to all of you.
I'm by nature so deep in love with challenges and making the impossible seem possible so probably getting OSCE3 before graduation is a good goal for me to chase right now :3 , btw here is my OSEP cert 
Thanks for reading my blog , if you have any further questions don't hesitate to contact me through Linkedin