I posted my policy's language at the beginning of this thread. Specific to that policy, it is at the time of placement.
Just use Comdex.
I personally try to go by S&P. They are much stricter than AM Best.
Currently, S&P has ZERO life carriers rated as AAA. I think there were just 2 rated AAA to start 2020.
AM Best has around 15 rated as A++ right now.
There are big difference between the ratings systems.
Fitch only has 8 AAA rated carriers. Moodys only has 5 Aaa rated carriers.
So obviously AM Best is more lenient with their top rank than the other big 3 rating agencies. With S&P being the most strict.
Just use Comdex.