Microsoft has actually started the process of herding those still running the Windows 10 October 2018 Update into updating to the most current November 2019 Update.
The same thing has actually already taken place to those running the April 2018 Update, and that previous forced upgrade scheme started in July (initiating automatic upgrades to the May 2019 Update, which of course was the most recent variation of Windows 10 at the time).
So this is the second time Microsoft has wielded an upgrade livestock prod, successfully, and the factor for doing so is security-- because completion of service date for the update in question is on the horizon. Users should for that reason update, or face losing out on essential security spots.
However, the timeframe in which Microsoft is pressing these obligatory upgrades is well in advance of what the company at first revealed. The main stance remains that the rollout procedure will be started "several months in advance of the end of service date to provide adequate time for a smooth update procedure".
Which is reasonable enough, however the end of assistance due date for the October 2018 Update is May 12, 2020, so that's really still over 5 months away-- a little more than 'a number of months' in our books.