Nick Fozzard has resigned from his post as Commercial Manager at Castleford.
His wife Sarah has also resigned from her post as Marketing Manager.
Interim CEO Steve Gill said: "It is with disappointment that we confirm the departures of Sarah and Nick from the club. I’d like to take this opportunity to thank them both for their efforts.
"The Membership scheme has been a fantastic introduction to the club and Sarah played no small part in its delivery. We wish her well.
"Nick’s transition from player to commercial manager was amazing to see. We hope that his next venture in life is prosperous and one that gives him fulfilment.
"The aim of all remaining staff is to roll our sleeves up and ensure the backroom team are in a position to make the most of the positive start to the season made by the players and coaching staff."
The resignations follow on from last week's departure of chief executive Steve Ferres.
With the glass ceiling to Super League being removed from next season, the path to the top flight opens up for Cumbria once again.
The Super League play-offs in their current form may attract some criticism, but they are keeping the season alive for several clubs in the bottom half.
The bonus point system, that has been in place in the Championships for the past eight seasons, is on the agenda for possible inclusion in Super League next year.
London Broncos have confirmed that Alex Walker has signed a full-time deal with the club.