There are a couple of threads on here that you can find via a search with thorough explanations of the chemical process that occurs regarding sodium hypochlorite and its affect on pH if you like reading chemistry. The more simple answer is that bleach is pH neutral, but it goes up then back down as hypochlorous acid is produced as it sanitizes. If you've minimized excessive aeration already, lowering TA is usually the best solution. The easiest way to do this is to keep adjusting pH back down into range as you've been doing, but each adjustment should reduce TA, and eventually, TA should be low enough that the pH quits creeping back up. At that point, your TA should be at the right spot for your pool to help maintain pH. Don't raise it back up unless you're planning on using an acidic chemical like trichlor, which could cause a pH crash at your new, lower TA level. But if you take care of your own pool and use bleach, there is no risk of a crash.
My TA is 60. I use only sodium hypochlorite, aka bleach. I have no drift.
My first season using TFP methodolgies, I had to adjust TA from 90 down to 50 to better keep pH in range. Someone here had to explain to me that I should quit raising TA back up into the recommended range despite what was officially recommended (TA was recommended 70-100 back then on the TFP chart; now 50-90). The range is misleading. One may think any TA level within the published range is fine, but actually, your pool has its own sweet spot.
When I used trichlor, I needed higher TA to maintain in-range pH, because trichlor is acidic. For whatever reason, beginning last season, 60 became my new perfect TA level (no longer 50). According to the great ChemGeek, pools have different outgassing rates and different source waters, and therefore TA can be manipulated to help maintain pH levels.
Now If you're source water has super high TA, or you have aeration that you can't reduce as do those with generators, you may still have to continually make pH down adjustments. This forum has become mostly a salt water cell generator forum; those operators mostly have to dose with acid regularly due to the aeration caused by the generator; but many bleach users only rarely make pH adjustments. Many of us have a very trouble free pool adding only bleach and cya for pool care. Too bad our method has lost favor. Your method is the most trouble free of all, because you have auto injection.