I'm not sure this is related to firmware, but my usage data disappears sometimes. I don't see what might be causing it. I hardly ever connect to a dock between charges and I always charge completely overnight. Some cycles the usage stats will stay but usually after a day or so I'll go look and it has nothing for usage or standby time. The rest of the stats are fine.
This is a week 24 8gb 1.1.4 ziphone unlocked on t-mobile. No other issues at all... Just curious.