You may want to wait a little bit to install Windows 8.1 on your computer, especially if you have apps that are crucial to your daily life. ZDNet reports that subscribers to TechNet and the Microsoft Developers Network won’t have early access to the final build of Windows 8.1, which breaks Microsoft’s long tradition of giving developers the final bits of new builds before their launch date so they can make sure their apps work properly.

ZDNet speculates that “the decision to withhold the RTM bits until launch probably does mean more folks will be downloading non-official RTM builds that will likely leak between now and October 18th” but adds that Microsoft is telling users to “wait for the ‘official’ RTM bits and expect possible patches and updates to the consumer preview builds that the company released in late June in the interim.”

But given that The Verge reports that a leaked build of the final version of Windows 8.1 has already popped up on the web, it may be hard for Microsoft to tell antsy developers to wait for another six weeks.