I ran into this problem with misaligned ticks and it seemed to require a fix in the jquery.flot.time library code.
I posted it as an issue on flot, with a patch chuck-h/emoncms@fadf28a, but maybe there is a solution within emoncms. There are a lot of corner cases in timezone stuff and I haven't even tried to test them.
flot/flot#1582

I ran into this problem with misaligned ticks and it seemed to require a fix in the jquery.flot.time library code.
I posted it as an issue on flot, with a patch chuck-h/emoncms@fadf28a, but maybe there is a solution within emoncms. There are a lot of corner cases in timezone stuff and I haven't even tried to test them.
flot/flot#1582