18 year old male gaining weight. Needs tips/clarification on ideal caloric surplus+when to change.

This involves weight gaining. I am now 18 years old, 5'11" and 146 pounds. I started at 130 and have been gaining weight with since July 6th, 2018. My maintenance for calories now is about 2600-2700 and its been almost a month since I've upped my calories by going into a caloric surplus of 3200 instead of my past 3000 from October-December. Since I first increased by 200, when youre supposed to typically increase by 500 should I up my caloric intake to about 3500? I haven't gained weight in the past 2 weeks and am just wondering if I should go up more or stay at 3200. I know gaining is all about patience but I was stuck at 143.4 for literally 2 1/2 months and don't want to be going through another plateau again. That change before from 2800 calories to 3000 calories helped me get past 143 and hit 146, making me think my actions were right and I was able to gain. Should i up my caloric intake about 200-300 more and see if I increase? Just for a little more background information I currently have 13.4% body fat and 20.7% body mass measuring today. October 16, 2018 I was 10.8% body fat and 19.6% body mass. I've also been hitting the gym 6 days a week, working chest/triceps, back/biceps, legs/shoulders x2. I am all set with gym and workouts just want a little help/clarification for caloric surplus ideas. Just seeking some help from people who have gone through long mass gain cycles, thanks. ANY OTHER TIPS will always be appreciated! (Got tired of being small so I've been trying to gain weight and build muscle mass)