How long do you usually run PPC campaigns to reach top rankings?

I’m curious to hear from experienced sellers: how long do you usually push your listings with PPC to reach top organic positions?

Here’s my current strategy:
I use TOP price for PPC (CPC), with the maximum daily budget Amazon will let me spend, targeting exact match keywords. Once I reach top positions, I completely turn off PPC and usually stay in the Top 5 organically for that keyword.

Before launching ads, I always make sure:

• My inventory is well-distributed across FBA warehouses in the US
• My listing is fully optimized for CTR and conversion
• I benchmark competitor CTR (I know how to check this), but I still don’t know how to verify conversion rates directly

I only launch ads if I believe my CTR will be at least 2x better than the competitors ranking at the top.

This strategy has worked for me in the past — in some cases, the product hit Top 3 within 3 days after launch.

Right now, I’ve launched a new product:

• CTR: 10%
• Conversion rate: 40%
• It’s been 4 days, and I’m still stuck at Position #28 (according to H 10), with no organic sales yet. I’m confident my metrics are better than most top listings, so I’m surprised it’s moving so slowly.

Here are my questions for experienced sellers:

1. How long do you usually keep PPC running before you hit the top rankings?
2. How do you decide when to stop or scale back PPC?
3. Do keyword rankings depend on sales in specific states? (For example, if I want to rank for a keyword in Texas, do I need to generate PPC sales specifically in Texas — and for longer?)

Would love to hear your thoughts and real-world experience!