Jerome.
Shoot for a year to gain 50Lb.s
If you fall short 10 or 15Lb’s you still have exceeded your goal.
DUring the next year period of time, do 2-3 planned out strength cycles lasting 8-12 weeks.
Consider some of the new and old training plateau busters ( negatives, speed, boards, chains, vary grips 0.
Work the assistance movements.
I don’t doubt you will miss a 50LB increase in a year. I thjink you can hit your 405 goal in your first 12 week strength cycle.
Aim for 415Lbs. If you fall short you shojuld fall to your goal.
If you missed by 10 Lbs. take 6-8 weeks to recoup, and do another strengt cycle.
Aim to overshoot the goal.
Some of thes 500-600LB raw benchers are happy to gain even 10-15 LB in a year.
For us “intermediates”, 50LB in a year is not impossible or implausible especially if you have never focused or trained for it exclusively.
During your training you will train auxilary movements ( tri’s, shoulders, lats ) so they get stronger too.