I always liked RTH; it's a great feature. But, you need to make sure your take off point and area within about a 50-foot diameter circle have very clear and distinguishing marking. A clear area without such marking will complicate the landing...
The December 23 date is related to licensing of new DJI models. It has nothing to do with imports of Care Refresh. It's not retroactive; it's about new DJI models.
And given that no audit has been initiated, the limitation on licensing new DJI...
When did IR beams start to triangulate distance between 2 points rather then echo response times to calculate distance? The IR beam must pass through any obstruction on the way out and also on the reflection return.
Was Amazon the seller/shipper? Many different business entities sell on Amazon.
If you had contacted Amazon within the return window there would have been no problem. A few years ago I purchased a Spark from a seller (Not Amazon.com) on Amazon...