Temperature moderate. Even if warm weather has been a problem, the script should fix that. My wifi time is the same as time.is.
Shortly after 11:00 (central eastern North America) May 27 I did a new GPS fix and uploaded the custom boot with the new code above in the last line. I checked the watch once an hour at some point between 9 and 35 minutes after each hour, from 11:09 to 23:10. The watch was on Clock A except briefly as noted below.
At 11+ to 18+ : accurate, fairly constant.
At 19+ : ahead by a second or a little more. No clue why.
At 20+ : still ahead by a second or a little more (same as at 19+).
At 21+ : I switched to Clock B. Surprisingly, the time was accurate, as from 11+ to 18+. I switched back to Clock A with no further change. It's unlikely that the sudden change was caused by my switching (see below).
At 22+ : ahead by a little (less than a second).
At 23+ : ahead by a little more (still less than a second in total). I switched to Clock B and back to Clock A again. Unlike at 21+, there was no change.
Of course, I don't know how the GPS timekeeper was doing over those hours. Nonetheless, the results from this one day are puzzling. (I'm not looking for a precision timepiece!)