It would be great to have a simple way to offset the time, relative to the strategy rules

We don't need it.
FSB takes time only from the bar open time of the historical data. Once you update the data files from your broker, the data will be with your time zone and exactly as FST will see the quotations from the same broker.

FST also uses time only from the ticks coming from MT or server time coming with the same data. Neither FSB nor FST use computer time or some external clock.

Be sure that offline historical data always corresponds to the FST data and you'll not have problems with time synchronization.

Hi Popov,

I have problem with a broker that I never had such problem with them before.

My stragegy closes every day before midnight GMT. Somethimes ago, the broker changed the server time to GMT + 3. When I use Day closing 2, I can manually set it to close 2:59. cloing is fine. However, because the indicator prevents any new positions to open after set closing time, no positions will be opened any more. Please help.