Flank Charge other Options?

[Bugle999]

Situation as below:

..............Pk..Pk..Pk..Pk
..............Pk..Pk..Pk..Pk
..XX..XX..Pk..Pk..Pk..Pk
..XX..XX..Pk..Pk..Pk..Pk
..............YY..YY..YY..YY
..............YY..YY..YY..YY

Pk is two BG's of 8 Pike facing down page in melee with YY.
YY is two BG's of 4 Legionnaires facing up page in melee with Pk..
XX is one BG of 4 Legionnaires facing up the page and in side to side contact with Pk - fighting as an overlap for YY.

My question is in relation to the options for XX.
They wish to get on the flank of the Pk so that they can fight with more than the current 2 dice and get the Pk disadvantaged for fighting in 2 directions etc.
etc.
a) Can they make a 90 degree turn right into front edge to side edge contact with the Pk - presumably this will only be a 1 element wide column?
b) If they can do a) above, do the Pk turn a base to fight and therefore get the minus of fighting in two directions - do they suffer any further disadvantage? Do they fight initially in the melee or impact phase?
c) If they can do a) above, presumably XX can expand one base width prior to the melee and therefore count 4 dice instead of 2. Do the Pk have to turn more bases to fight the new expanded base that has contacted them on the flank?
d) if the above is not allowed, can someone tell me how best to exploit the situation so that you make best use of the currently overlapping unit XX.

MTIA.

[pbrandon]

See pages 76-78 for your options here.

Paul