From the rules:
2.2 Blitz Phases
Your participation in the Blitz phase depends on what kind of Blitz action you select. All of the Blitz choices except the Free Blitz will require that you expend Oil. All major powers on a side must announce which Blitz action they are selecting before any major power begins Blitz activities.
All major powers on a side must announce which blitz action they are selecting before any of these major powers begin Blitz activities?
It seems to me you intend to rule that all the powers on a side must declare their blitz actions if any before they act, but it could be read as before any power acts. Which would mean the Allies would have to declare their possible blitzes before the Axis begin to play theirs?