@Coty84
the way I see it, the SFL preparation is very specific to each individual.
A good article full of valuable tips:
How to Prepare for, Pass, and Get the Most Out of the SFL | StrongFirst
Where are you at the moment with the strength requirements ?
I have never done 5/3/1 myself, but for what I know about it, it should give you a good and lasting base for meeting the strength requirements by July. If you like it an it works, keep going.
Ensure that you also practice the lifts the way you will be tested (see article above).
I have no statistic, but at my cert, people failed mainly because of strength. At the strength test of course (myself and my pitiful bench included), but also at the technical test with the military press. It always surprises me to see someone who can bench 1,25BW struggle with a 2/3BW press, but it is what it is. So don't forget to build a solid press the last few months if you don't have one already.
How comfortable are you with your technique for the 3 technique tests ?
Even though they seem easy, the focus is technique. I have witnessed quite a few no-counts because of a high squat or a rounding low back. Ensure during your training that you build a proper lift, not just a heavy lift.
My own experience is that you can be fooled by the apparently light weight. At 70kg, I can do sets of 5 with more than twice BW, so the technical 105kg was really light. I did not respect it, lost focus and had a no-count for low back rounding! I can tell you that for the remaining 2 or 3 reps, I wedged properly and kept my back flat!
Work capacity
The SFL is not as draining as the SFG, but we lift a lot, and heavy! After each teaching segment, we practice the lift with light weights, and then we have the opportunity to work heavy. Many will go for a heavy single. Be prepared for it.
Good luck and enjoy the journey!