18038 DD Movement Keeps going out of Spec

[TheWatchmen]

Hello,

I wanted to ask for thoughts/possible reasons that my 18038 DayDate might continue to drift/ run out of spec every three months or so.

The 3055 caliber movement was fully serviced when I picked up the watch in Feb of this year.

It was out of spec by about -10 per day in May, and I had it regulated under the 2 year warranty.

It went out of spec by about -20 in August/September, so I had it regulated again.

Fast forward to today, and now it’s about -8 per day, after running at +1 for a few months since it was last regulated.

I wear this watch daily, and am fairly active but take it off at night.

I can and will have to have it regulated yet again, but has Tools or another watchmaker here ever seen this or have thoughts as to why this would keep happening, notwithstanding accidentally knocking the movement?