A supposedly leaked internal document reveals a wealth of information regarding Apple's fall product lineup, including the names and release timelines of new iPhone, Apple Watch and iPad models, operating system release dates and more.

The allegedly leaked paper, titled "Apple Software Development Resources," was created for perusal by Apple employees, the company's engineering team, retailers and contractors. Twitter account "AppleBeta2019," which has in the past provided accurate information regarding beta versions of Apple's various operating systems, reportedly obtained what is referenced as a "September newsletter" by a contractor on Tuesday.

AppleInsider has reviewed the 10-page document in its entirety and while the information is compelling, certain details are inconsistent with previously confirmed leaks. As such, we are unable to vouch for the note's authenticity and offer the following merely for purposes of discussion.

According to the resource, Apple will announce three new iPhones this fall, dubbed "iPhone 11," "iPhone 11 Pro" and "iPhone 11 Pro Max," branding that corresponds to previously reported internal identifiers "N104," "D42" and "D43," respectively. Apple's alleged naming scheme would more closely align the company's mid-tier LCD iPhone model with high-end OLED variants.

Each of the new handsets are said to ship with iOS 13.1.0 standard, a beta version of which was seeded for testing last week. Whether the first batch of devices will come with iOS 13.1 pre-installed is unclear, as the document goes on to say the new phones will receive a security patch designated iOS 13.0.1 as their first over-the-air update sometime in October.

Wording in the publication hints at a Sept. 27 launch date for Apple's new iPhone 11 series, with users supposedly able to gain access to iOS 13 on Sept. 23. A subsequent security patch is slated for release in the days following, while iOS 13.1 will be available for public consumption in October.

The quoted timeline is unconventional for Apple, which typically unveils new iPhones at an event on Tuesday, initiates preorders that Friday and commences deliveries and brick-and-mortar sales a week later. A next-generation version of iOS, in this case iOS 13, is pushed out to owners of legacy hardware the Monday after preorders go live. If Apple holds to that schedule, and the document is legitimate, this year's iPhone lineup will hit store shelves on Friday, Sept. 27. Alternatively, the new phones could arrive on Sept. 20, before iOS 13 is issued to the public.

In either case, the document points to a release schedule atypical of Apple's usual patterns.

As for Apple Watch, four new models are tipped for unveiling at a special media event on Sept. 10, with a launch presumably coinciding with iPhone. Specifically, model numbers A2156, A2157, A2092 and A2093 will ship with watchOS 6. An expected watchOS 6.1 is due in October.

Two new iPad models identified as A2068 and A2198 are pegged to ship in October, potentially signaling an announcement concurrent to that of iPhone next week. Alternatively, Apple could hold a separate event for the tablets' unveiling as it did with the third-generation iPad Pro in 2018. The document suggests A2068 will be marketed as an entry-level iPad, while model number A2198 will be an iPad Pro successor. Both are expected to ship with iPadOS 13 pending a stable release of iPadOS 13.0.1.

Interestingly, the document says iPadOS 13.0.1 beta compatibility will initially be limited to the forthcoming iPad Pro, with lesser models not able to access the software until subsequent beta versions are released.

Finally, macOS 10.15 Catalina is pegged for release in alongside iOS 13, iPadOS 13, watchOS 6 and tvOS 13 on Sept. 23.

Apple is widely expected to unveil its latest iPhone and Apple Watch hardware at special event at Apple Park on Sept. 10. AppleInsider will provide full coverage of the announcements.