As I read the rules:
Itīs considered a normal CC for both of the models, so all rules apply. You still would have to use the CC stats of a secondary weapon and not the PB for a "ranged" combat. Seems a bit weird, since polearms are two-handed, but it gives the point.
Itīs a normal CC. So the models canīt auot-breakaway. Only the range of the combat is modified.
The real problems come on further thinking through the whole matter.
As the model is one inch away from the opponent he can only strike back with a range of at least one inch. So since itīs a CC he cant use a ranged weapon AND no CC weapon if not also a polearm! Since normally the models carry only weapons for base-to-base CC you can outmaneuver them......
they have to make a move action, which isnīt a problem, since they have to charge you anyway to come into CC BUT if they want to move they have to make a break-away....!!!
Thatīs fantastic.
Never thought of this use of Polearms to lock the opponents in CC...
The opponent even hasnīt the chance to countercharge, since your model stops at one inch away from it. I mean countercharge is possible, but useless, since the opponent canīt strike back within reach!
Only possibility is to brace for the charge to nullify the bonus.
AND on top of that the models are safe from sweep-attacks since they canīt reach either. Even with a break-away combined charge-action it will be hard to get into contact with more models....
Funny thing as I think of that.
Oh I want to test these Valkyres and Vestals with the Spears

EDIT: Forget the bracing, thereīs no bonus to the charge anyway...