Anxious about first performance review

This question is specifically for Meta folks, so looking forward to hearing from y'all.

I just joined Meta in March 1st week (bootcamp) and joined my team, in mid march as an E5.

I already have had a manager change, the guidance from my first manager was that the expectation from me is to always be able to unblock myself and keep making at least 1 small fix per day during my onboarding.

I have had quite a bit of trouble understanding the tech stack though, getting acquainted to Mono repo was definitely tough. Plus all of the tools within meta are specific to meta. So I've not been able to land at a 1 change per day cadence.

But with the new manager, we have not set up any official expectations yet but they seem to be quite high compared to the previous manager. This manager seems to be very impact focused and not very productivity focused.

I'll only be able to land 1 project that will give me some impact credits and 1 that will count towards engineering excellence, that gets rid of some tech debt. My diff count optimistically speaking will be around 50 by end of June. But I haven't written the best of code since I'm new to the framework. I don't quite have a lot for direction and people axis. I've heard from some folks that people axis isn't expected from newbies but haven't heard that officially from my manager himself.

I tried quite a bit to generate scope for myself, came up with a proposal and it got traction but it wasn't prioritized by the management and hence I won't be picking it up this half, so I won't have another project to work on till end of the half.

The team seems to also be struggling to meet their H1 goals and things seem quite dire for us. I may have some immunity because Its been 3 months only for me so far, but someone who joined around the same time is doing better than I've done.

What should I expect from the first PSC? How scared should I be?