The developer, at risk of losing up to 50% of its global workforce, has moved the expansion's release date from August 28 to September 11.
"As you may know, this week has been a challenging one for everyone at Funcom. We initiated a process of reducing costs after the launch of The Secret World and this has naturally affected the production schedule as we work on readjusting the team and our internal development processes," read a statement from the studio.
"As such, we have had to give ourselves a little more time to wrap up Issue #2 and the new release date for this update is September 11, 2012.
"We appreciate your understanding and we apologise for the inconvenience. We are definitely eager to get this update out the door so that you guys can finally get your hands on that awesome rocket launcher."
The 'Issue 2: Digging Deeper' expansion adds new character customisation options through the plastic surgery and barbershop services, additional investigation and action missions, as well as rocket launchers.
The Secret World was release for PC in early July.
> Read Digital Spy's review of 'The Secret World'
Watch a trailer for The Secret World below: