Approval of the contest is pivotal to Klitschko accepting a December 10 fight in the UK against IBF title holder Joshua, with a decision initially expected on Thursday and then delayed to Friday.
WBN have now been told the final ruling could be made public as late as Saturday whilst tallying is verified and everything is rubberstamped.
Should Klitschko be given the green light to contest the vacant WBA belt against Joshua, a trio of championships could then be on the line in six weeks time.
The IBO are the third organization ready to be involved, although everything hinges on the upcoming announcement by WBA President Gilberto Mendoza.
In other news regarding the fight, WBN understands that Eric Molina is preferred to David Price as a replacement for Joshua should Klitschko go elsewhere for his next bout.
Aussie Lucas Browne is the frontrunner to oppose Klitschko in Hamburg despite denials of any further talks by the former world champion’s lawyer Leon Margules.
It’s hard to see how the December 10 date will be workable for Klitschko though if the ex-ruler is required to open further talks with Browne over the weekend, meaning the easier decision would be to sanction the Joshua fight in order to begin promotional duties.
Browne could then contest the regular or interim strap against either Luis Ortiz, David Haye, Fres Oquendo, Alexander Ustinov or Manuel Charr – dependent on who is available.
**Information correct as of 18:25 ET / 23:25 UK on Friday, October 21**