The statement from Acer then, from Windows United (translated from German):
Unfortunately, the Anniversary Update for the Acer Liquid Jade Primo leads to instability of the operating system. As the satisfaction of our customers is our number one priority and the current version is technically flawless and resilient, we have decided to refrain from an update after thorough consideration.
What a load of codswaddle. They're saying that Windows 10 Mobile 'Threshold' is 'technically flawless and resilient'? This is the OS branch that the Lumia 950 range struggled on for months at the beginning of their lives?
The Anniversary Update (a.k.a. Redstone) is far more stable and functional than 'Threshold' (builds 10586.xx) and any instabilities can only be down to bugs in the Acer firmware, surely? Or maybe Acer is just making an excuse to avoid putting in some actual work in testing and approving the OS update?
The Jade Primo was never the star of the Windows 10 Mobile world, it was eclipsed the moment the Lumia 950 range was available - and the Jade Primo had been getting more and more left behind as time went on. And now it's official.
As MSPU points out, mind you, anyone who does have the phone can just slap it onto the Insiders programme - in which case the Jade Primo can run with Redstone 2 and beyond. Take that, Acer!