Note that I posited that the Chinee balloon may have given DARPA the opportunity to get rid of “beta” versions.
The Alaska 'device' seems to be similar to the Lake Huron intruder. How did the Great Lakes intruder go undetected for so long? Where did it come from? As you say, maybe launched on U.S. soil - ? I posited yesterday that the 'unknown radar anomaly' over Montana was the same that closed northern Michigan air traffic and was then shot down over Lake Huron... following the US / Canadian border all the way! Supposedly un-traced!
What took so long to locate the intruder? ... which, as you say, is 'octagon shaped'. Doesn't sound like stealth material.