Changed my IsoMax overhead pressing technique

To perform the Overhead Press on the IsoMax bar, I was doing the following:

1. Squat slightly so I can get my chest under the bar.
2. Pull the shoulder back then pull the elbows down.
3. Begin applying the zip-up technique, starting from the feet and working up the body.
4. As the zip-up is applied, I start feeling force connected from my feet to my hands. This is influenced by previous practice of the jin skill, though folks the six-harmonies space would call what I'm doing "muscle-jin". In this case though I'm not training for 6H martial arts. Rather I'm using muscle-jin to create whole-body tension between the bar and my feet. The resultant force eventually get high enough to make the IsoMax bar start beeping.
5. When the bar starts beeping, start pressing the bar upwards with the chest, arms, and shoulders.

At the point that the bar starts beeping, my body position is close to what it would be if I were pressing double kettlebells The low back and legs are straight. The upper back is not straight because the chest is pulled forward and up and the scapulae are retracted and pulled down.

So the change to my IsoMax pressing technique is this: In Step 5 above, when the bar starts beeping, I think of increasing the pressure of the feet against the IsoMax footplate, by tucking in the tailbone more, squeezing the glutes harder, and unbending the upper back.

On the first day I tried the new technique, my max force on the last rep was 92 lbs. which was a jump of about 15 lbs. of force compared to the old technique