Change to:

‘Each time an IMPERIAL KNIGHTS unit from your army Advances, until the end of the turn, ranged weapons equipped by IMPERIAL KNIGHTS models from your army have the [ASSAULT] ability.’

Change to:

‘TARGET: One IMPERIAL KNIGHTS unit from your army that has not been selected to fight this phase.’

Change to:

‘TARGET: One IMPERIAL KNIGHTS unit from your army that has not been selected to move this phase.’

Change to:

‘TARGET: One IMPERIAL KNIGHTS unit from your army that has not been selected to shoot this phase.’