The Commonwealth originally indicted Banfield with four counts of aggravated murder, because Virginia law permits them to charge aggravated for two murders within the same transaction as well as two murders within a three year period.
§ 18.2-31
A. The following offenses shall constitute aggravated murder, punishable as a Class 1 felony:
[...]
7. The willful, deliberate, and premeditated killing of more than one person as a part of the same act or transaction;
8. The willful, deliberate, and premeditated killing of more than one person within a three-year period;
law.lis.virginia.gov
The Commonwealth was waiting to see how Banfield testified before deciding which one of those two they would proceed with, because while they can have both in the guilt phase of the trial, the judge can only sentence on one of those counts. They thought it could be confusing for the jury to have both.
Yesterday the Commonwealth asked the judge to dismiss the two counts (one for each victim) of within the same transaction, and just leave the two counts (one for each victim) of within a three-year period. The judge then pointed out that they probably shouldn't have two counts (one for each victim) for the three-year clause, because aggravated murder requires anyway that two people were murdered.
The Commonwealth is considering overnight how to proceed on this, looking at case law. They are not dropping aggravated murder, but they will confirm if they still wish to withdraw the same transaction charge, and also provide clarity in the jury instructions for if the jury decides that he murdered one but not the other, in which case under their waterfall instruction it falls to first degree, not aggravated, for just one victim.
That's my understanding.