When Can It Be Waxed?

Why? would it cause any problems?
It won't cure as fast, could scratch paint, chemicals in covers, trapping vapors. If you overthink stuff.

In my painting book I read years back, it said not to use car covers, set anything on the paint, wax it, wash it with anything except water etc., until it's 100% cured. And thick paint can take much longer than 6 months to cure, as I discovered on my first paint job.
Here's a test, smell the paint, does it still smell like paint? If so, I consider it still not cured.
Parked in the sun every day in New Mexico things cure pretty fast, unless you make mistakes like I did. I had shrink cracks show up 20 years after painting but I consider it patina.