Update 2018-09-07: Michael Niehaus was kind enough to supply some additional information on this subject. So to clarify this post and the information from MS. The currently available versions of Windows 10 Enterprise and Education will have 30 months of support and future releases starting with 1809 and 1903 will have 30 and 18 months of support.
Niehaus has also stated that Microsoft is still commited to deliver innovation and new features for every single Windows 10 release.
So its happend again, the lifecycle supportstatment surrounding Windows 10 has been changed. Some say for the better, but it remains to be seen. The change only applies to Enterprise and Education SKUs and only to the september relase of every year. So if you are on 1703 nothing has changed but if you are on 1607 or 1709 there has been some changes.
The new change is that Enterprise and Education now get 30months of support. There is also a small note to be made about a statment of the lifecycle facts page stating
“…you’ll need to install the latest feature update to help keep your device secure and have it remain supported by Microsoft.”
Which would mean that unless you apply the latest CU every month you are not really supported. How this will be “enforced” remains to be seen.
For more detailed information and source of the change review the lifecycle fact page from Microsoft here https://support.microsoft.com/en-us/help/13853/windows-lifecycle-fact-sheet
One last thing to note, up until now Microsoft have only been testing upgrading the previous version to the lastest version of Windows 10, example when 1709 was released the only path that was tested was 1703->1709. With the new support statement you might have an urge to skip versions. However unless Microsoft changes their test protcoll and actually tests jumps like 1607->1709 it might still be worth going with every version, altho not as quickly as before.
Support dates as of 2018-09-06