Seibold is the front-runner to take the Sea Eagles job, and while the club are yet to make an official announcement, it's believed the deal is as good as done.
Seibold has a friendship with club chairman Scott Penn, having previously served as an assistant coach before landing his first head coaching role at the South Sydney Rabbitohs.
The coach has been out of the game since being let go by the Brisbane Broncos, and has since worked in rugby union - something that is likely to delay him from arriving on the Northern Beaches should the deal be done.
Regardless, The Daily Telegraph are now reporting that attention has turned to confirming Seibold's staff, with a shock name in England rugby union coach Eddie Jones set to join Shane Flanagan and Laurie Daley.
Jones has previously admitted he would be open to an NRL job, although it's unclear if he would leave his current post, where he is contracted until the end of the 2023 Rugby World Cup. Jones has, however, confirmed he will step down from his England role after that tournament.
It's believed a number of roles are potentially being discussed for Jones, ranging from part-time advisor to head of football.
It's understood Daley could be used in a similar role by Manly, with the duo both on a hitlist for the Sea Eagles as they build a revamped staff to work with Seibold.
The club have touted changes, with Scott Penn saying last week before Des Hasler's sacking that the roster should in the premiership hunt, and that a football department to match was needed.
Shane Flanagan, it's understood, would be considered for an out-and-out assistant coach role. He is the director of football for Papua New Guinea at the Rugby League World Cup, and holds a recruitment consultancy role for the St George Illawarra Dragons in the NRL, but has made no secret of his desire to return as an NRL coach in the future.