Import triggers blocking warning "The structure of the data file for the layer "xx" has changed"

There is a change going out with the 24.6x21 BETA later today that will remove the warning dialog. Hopefully that'll help with this situation. 

For anyone concerned - the workaround for this is to _only_ have the json as footage in your project, and _not_ add it as a layer anywhere. This avoids triggering the parsing for the properties tree that show up when JSON is presented as a layer.
However this means that you have to reference your JSON from footage rather than pickwhipping from the properties tree of a JSON layer.

var brands = footage("brands.json").sourceData;
brands[whatBrand+1].name;

If you want to export as a mogrt or reduce your project, you will need to include the layer in your comp, or the json file will be omitted from the mogrt.

Please do not hesitate to reach out if you have problems reproducing the error

I'm looking at this issue right now.