Oh man I hope LRB did not stay up for this one.
Dave
And it seems to track the mileage from the beginning, apparently due to its internal accelerometer.
Here's a fun fact I discovered about the 225. If you are running in your garage on the TM and forgot to turn GPS off, so it can "kinda" get a signal, it will track the "distance" you run between the street outside your house and the neighbor's back yard, and you will get a nice report on how you ran at a 20:00 pace with a HR well into the "aerobic" zone.
I did that with my 405. I happened to glance at it about 25 minutes into a run and had gone .1 miles. Map bounced between my house and two neighbors houses.