HYG Still Being Used

The SPY arbitrage model runs at least 30 minutes delayed so what is happening at this moment is unknowable from their end, but from what I see, HYG is still being used. My question is whether it is to slow the rate of decline in the market or arrest it, or whether it's being used to try to push the market higher intraday?

HYG

HYG vs. SPX

From the SPY and DIA intraday charts it seems it is being used to lift the market intraday, not so much on the IWM and QQQ charts.