The latest MetaTrader terminal build changes how the strategy tester generates ticks in the "every tick based on real ticks" and "1 minute OHLC" modes. Backtests produced before the update are not directly comparable with new ones.
Strategies that scalp inside the spread or rely on intrabar entry order are affected the most. Grid and averaging systems usually shift slightly, while swing systems on H1 and above barely move.
Our recommendation: re-run the optimisation for any parameter set you took from an older report, then compare walk-forward results rather than a single equity curve.
All expert advisors in our marketplace have been re-tested against the new build, and the published reports were regenerated on the updated tester.