my JLC Master Home Time did just as well. I'm sure it's the very favorable temperature these past few weeks, 23-32C max.. In Thailand recently, temperatures of 35+ in the day time, the JLC picked up 6 secs in 4 weeks. On the UN Marine Chrono: the 118 movement is very stable so far. And, yes, it was off by exactly 24 hrs, but adjusting the date does not change the time!