Question

I had my pmax campaign going for about two months. I set the target CPA to six dollars, it was hitting six dollars, but I set that conservatively cause I really need it at five dollars. 

For the most part it’s optimized. I paused it yesterday for half a day and I started other campaigns with similar products. I think I paused an asset once and then reactivated it. If I change my target CPA from 6 to 5, what will that do to learning or optimization? It’s been hitting the six dollars for the most part and hitting my budget. If not going over my budget on some days.

Answer 1

Changing your Target CPA from $6 to $5 will absolutely impact optimization, but it doesn’t reset the campaign into a full learning phase like restarting would.

Here’s what usually happens:

• Meta’s algorithm will tighten its delivery window — it’ll try to chase cheaper conversions, but you may see a drop in volume (fewer conversions, slower spend) while it searches for lower-cost users.
   

• If your account history shows you can sometimes hit $5 naturally, then it might adjust gracefully.
   

• But if $5 is too aggressive for the current audience/data, it could throttle spend and underdeliver.

What I’d recommend:

• Instead of dropping straight from $6 → $5, test $5.50 first for a few days and monitor performance.
   

• Watch ROAS, conversion volume, and delivery.
   

• Avoid too many changes (like pausing assets, budgets, or reactivating things often), as Meta may slow re-optimization.
   

You're doing the right thing thinking cautiously — gradual changes usually keep things stable while still pushing toward your goal