GPS flakey after latest s/w. 19.18

Can‘t confirm, working fine for me with 19.18

PeterPrestonGreen said:

not properly starting T arc at top of new activity stays red + not the full arc.

That is the key factor.

Check „settings“, „system“, „info“. Scroll until you see „Ephemeris“. This contains information about GPS constellation of the upcoming days.
If it is outdated, your device will have a hard time getting a GPS fix („red circle“).

You could trie to connect the watch to Garmin Express on PC or Mac to try to force an Ephemeris update.

Any synchronization operation, whether using WiFi, Garmin Connect app, or Garmin Express (PC or Mac) will update the GPS ephemeris tables.

If you can't do that, prime an activity and leave the watch with a clear view of the sky for about 10-15 minutes until it gets a lock.

It will receive the ephemeris data from satellites that way. However, that doesn't also include the localised AGPS data which speeds up GPS lock from minutes to seconds.

I sometimes have this on my FR255 and if I press BACK to leave the start screen, then START again, it usually gets a lock quickly. This is with current ephemeris and in the same place and similar times (within an hour or two) where I usually start a daily activity with clear skies.

For me, it has been happening sporadically for a lot longer than just firmware 19.18

Kind of a tangent, but I wouldn't trust the green ring to indicate a *solid* lock, especially if you're in an area with a lot of tall buildings.

In my experience, the faster the green ring appears, the faker it is. I can see this easily by the fact that immediately after I see the green ring, my pace is changing wildly (and my position is changing on the map screen) even though I'm standing still. I usually have to wait a few more seconds (sometimes up to a couple of minutes) for the pace to settle down.

If I start running as soon as the green ring appears, I usually have bad GPS data at the start of the run (extra distance / paces that are too high).