Backtesting and DST

Confused about backtesting different date periods in an EA and DST on MT4

If a server iscurrently running on (EST) = GMT-5
and the dates I want to backtest is between april 2009 to november 1st (all within the EDT range)

Then I should change any manuall GMT offset of any EA to Eastern Daylight Time (EDT) = GMT-4 for the purpose of the backtest?

Thanks in advance
Pckeys