It's amazing how differently some ARFs work for different modelers.

I'm flying my H9 with the CG around the 5.4" location. It's an excellent flyer. And handles on the ground really good for a taildragger model with it's wheels so far aft.

The CG computations showed a range of 4.3" to 5.4" for me. And the flying field that airplane will taxii around on most of the time is anything but smooth, so it's CG was located as far aft as possible. I knew it'd be flyable although it's elevator would be sensitive, and the elevator pushrod has been moved out on the horn a step.

It is very interesting that the response you saw to begin with was so odd. To not respond to input for so long and then suddenly respond really doesn't sound like a trim problem. But what the heck, you've got it flying and you can't argue with success.