As market turned into bullish again, my April income portfolio showed a Delta of -38. The RUT double calendar position had its price in the right slope area as shown below. So an adjustment is necessary.
After these adjustments, the new portfolio has a Delta of -19 (a reduction by 20) and Vega of -218 (equivalent to a Delta of +20 approximately). If SPX increases another $15, I might have to do some adjustments again.