Yep, the GPS V will reduce the track to 250 points if you save it.
Also, if you have an old III+, when you upload tracks it will stick them all in the active log as one big track (no provision to save tracks other than the active log). The III+ can still be useful like this. I just used to turn off the tracking so I didn't overwrite my uploaded track. Downside is you can't record a new track while riding then.
R-dubb, this is probably the best explanation of Garmin tracking I've seen.