A few months now (maybe a year and always with the latest version installed on my 255s) i noticed that it counts floors that i have not climbed.
Previously I was climbing daily at least 8 floors to my office plus 3 to my apartment. a total of 11, sometimes counted as 10. Fine with me.
Also counted extra floors during the day, inside shops, etc. Amazingly accurate.
At some point -as i understand - it started counting (milder) elevation changes also, and not just stairs.
So now it sure counts floors but also counts uphill walking as floors. Suddenly i reach my goal of 10 floors even when really climbed just 3.
Just leaving that here for others that noticed it or the tech guys.
Thanks.