Daylight savings and backtesting

I have a question, recently i have gotten into forex and have started backtesting a strategy in wich i use the highs and lows of recent sessions. Now i have just been using 12am utc for open of asia session, 7am utc for london, and 1pm utc for new york. I have been using these times for the whole year but i am wondering if i have to use daylight savings to correct the times and that way take better trades, if i do have to consider daylight savings could someone explain to me when i have to use it and what times i have to use?