Timefilter and timezones issue

Hello
I have a grafana v5.0.3 + influx db set up. Time in influxdb is in UTC and i’m mostly using the time range “Today so far” in Grafana

Here in Europe, the dashboard is working perfectly, but for my colleagues in Hong Kong, when they are looking at “Today so far” range, they are getting data from the whole previous day and for the current day too.

Example
Today 11/08/2018.
In Europe in the dashboard i retrieve only the data from 11/08/2018 00:00 UTC time to now
In Hong Kong with “Today so far” time range, they are retrieving the data from 10/08/2018 00:00 to now (same data as if in Europe we choose the time range the last 2 days)

I don’t know where I could manage to override the wrong $timefilter

Thanks for your help !