Confusion about Stuart Lancaster's role but Leo Cullen stays the boss

The question arose with the club’s press release which announced Lancaster’s one-year appointment as a ‘senior coach’ rather than as the like-for-like replacement for defence coach Kurt McQuilkin who has this week moved home to New Zealand.
Cullen was straight up in declaring Lancaster’s primacy on that side of the ball for the season ahead, but then the new man went on to expound about a broad church of interests that extends to an attacking brief and his background in elite player development.