I mean, splitting a bay equally in two and in 3 isn't the same.Should be 3 from what they have said. In any case, it seems confirmed that it can carry MRAAMs in the side bays, definitely a good feature. The loadout shown in the image below is quite nice for a strike mission, me thinks:
Suspension points/adapters for two bigger&heavier munitions may not be the same points that are used to hold lighter and narrower 3.
And they may not be used simultaneously. Or may actually be - for something very small.
I see no other explanation on the given airframe.