I can see this working on my end in nt8. The following was appended to the SampleATMStrategy. If i run this on a 10 second chart it places the targets and then on the next bar close it moves both targets.
if (atmStrategyId.Length > 0)
{
if (GetAtmStrategyMarketPosition(atmStrategyId) != MarketPosition.Flat)
{
Print("Changing targets");
AtmStrategyChangeStopTarget(0, Low[0] - 20 * TickSize, "Stop1", atmStrategyId);
AtmStrategyChangeStopTarget(High[0] + 20 * TickSize,0 , "Target1", atmStrategyId);
}
}

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