Staring SSLP after years of lifting

I’ve been lifting for about 4 years now. After doing bodybuilding bro-splits and having terrible results, I started 5/3/1. After listening to you guys talk about 5/3/1, I decided to start the SSLP. I can press, bench, deadlift, and squat with relatively good form. Being that I am not a complete “novice”, how do I assess what weight I should start with and how quickly I should progress in weight? My lifts are 225/170/305 and 100 press (yes those are in lbs).

Also, I am able to do multiple chin ups. Which phase of the program should I begin with?
As a side note: I am training in hopes of competing in my first powerlifting meet around August 2018. After SSLP I will begin The Bridge program. Thanks

You need to purchase the book, Starting Strength: Basic Barbell Training 3rd Edition, and read that. As far as selecting the initial load, you’ll pick a load where the bar speed slows down for a set of 5 but your technique is still perfect. That’s where you start.