Microsoft is reportedly yet to finish its forthcoming Windows Phone 8 operating system and is having to work overtime to get the software finished.

According to The Verge, multiple sources have suggested that the US software giant had originally planned to launch WP8 in early October. However, delays and bugs in testing have led to the company now aiming for a launch at the end of that month.

Microsoft is expected to sign off on a final version as early as this week but delays could ensue as manufacturers and service operators run through their own tests of the platform before giving it the approval to go public.

The recent launch of the Nokia Lumia 920 and 820 saw devices on display running Windows Phone 8, however, attendees were prevented from getting hands-on time with the phones due to the fact that parts of the OS were still unstable.

Similarly, at the recent launch of the Samsung ATIV S the company was not able to show Windows Phone 8 working on the handset, with demo devices instead shown with static WP screens.

Despite the delay, sources are suggesting that the momentum of Windows 8 and extensive advertising campaign planned for the Microsoft Surface tablet should still ensure a high level of exposure for Windows Phone 8.