What about NOT decreasing rated range?
While my daily 90% charge level has dropped from the original 242ish that it started to around 231, and my "usual" range charge has dropped from 272 to ~258 miles, what I've found, at 39,500 miles, is that after a long trip and a full charge (allowed to range charge until the charging actually completed that hour-long last minute) that my range numbers improve dramatically, and they seem to be real. These photos are from this weekend. I range charged to 258 miles prior to a trip to St. Louis (about 225 miles all interstate), arrived with about 8 miles left, charged to about 80% overnight then topped up yesterday afternoon and hit 273 miles rated! Even my 90% rated range has increased back into the 240s it appears.