This was a first...reminded me of the old days with my FR210...
up until now, i get GPS lock in just a few seconds (5-10?). but today, for some odd reason, for my usual work run, it wouldn't lock. i checked the map and it showed me at my last location (home) which is about 15miles away. i patiently waited, did some extended stretching and nothing. so i finally rebooted it.
of course, in rebooting, then as fate would have it, when i hit the start button to get to Run, it got itself into the restart loop which i was able to end the 2nd time by hitting the light button on the 3rd time it restarted.
i hit Run, and again, it took a while to lock. getting impatient after about 30 seconds, i changed from my typical All Satellites to Multiband and boom, it locked very quickly. i then switched back to All Satellites and it it showed a green GPS lock after 1-2 seconds.
the run then proceeded without a hitch but this was certainly a surprise experience as i've had the watch since early june and done many runs without having had this issue crop up. (i did have one incident early on where it failed to reacquire GPS lock (for GPS only mode which i have since abandoned) after hitting pause at traffic light...but since then, its been stable in this regard)