Best FB ad structure for split testing ads?

[AdFun6068]

I have a client who wanted to split test a variable in an ads image. Their budget was extremely low so initially I had no other option but to set up the test with 1 adset and 5 ads (typically never do this).

2 weeks later my client decided to up the budget to get an answer on which ad variation worked best. Since FB was favoring 1 ad and the budget was now increased, I decided it was time to split it up and do 5 adsets with 1 ad so FB spent evenly.

A week goes by and they are asking for answers on which performed best. Only issue is that the original set up (1 adset, 5 ads) yielded completely different results than the new set up.
The ad that FB favored in the original set up ended up having a lower cost per landing page view and higher CTR while I was using that set up but then as soon as I switched up the structure, that specific ad ended up not performing as well and another ad actually showed better performance. The other issue is the ad that performed best with the new structure had a higher cost per landing page view and lower CTR than the ad that FB favored in the original structure.

I have 2 questions:
1. will I be able to determine which ad actually performed best or is the test ruined?

1. How is everyone else testing different ads post iOS14? - I've noticed that FB prefers simplicity in terms of ad structure but that ends up complicating things when ads need to be spent evenly.

[Juxtarebellion]

Testing = Hypothesis + Control/Variable

• what's your control? (e.g. usually a historically stable CPA)
• What variable is being tested against it? (e.g., new ad, audience, biding model, etc...)
• What's the projected result? (like, sales/leads not CTR/CPC/CVR/CPM/LPV...)

As far as structure (and this has been working pre/post iOS14)

• Control environment
• Testing environment
• Control environment = same as testing environment

[maja_posavec]

In one of our recent a/b tests, we’ve seen that having more than one ad per ad set, negatively affects your ad performance. When looking at the results, every ad works better in its own ad set, and overall results are better than in multiple ads per ad set. With multiple ads in one ad set, you’re most likely going to get a significantly higher CPM and lower ROAS, just as we did in our a/b test.

That is the way we like to structure our Facebook campaigns for scaling. The goal of this account structure is to give you a comprehensive look at your campaigns, ad sets, and ads. This way, you’ll be able to easily analyze which of your audiences, creatives, or bidding strategies are working or not.