Nikon issued a new service advisory for the Nikon D750 shutter issue expanding the number of impacted cameras: now the Nikon D750 cameras manufactured from July to September 2014 and from July 2015 to September 2016 could also have a faulty shutter.
You can check if your D750 serial number is impacted here.
Here is the full text of the service advisory via Nikon HK:
NOTICE TO USERS OF THE NIKON D750 DIGITAL SLR CAMERA OF NEWLY ADDED AFFECTED PRODUCT SERIAL NUMBERS (UPDATED)
In July 2015 and with an additional notice in February 2016, we announced that the shutter in some Nikon D750 digital SLR cameras manufactured between October 2014 and June 2015 does not function normally, sometimes resulting in shading of a portion of images. Since that time, further examination of the issue has found that the same issue may also occur with D750 cameras manufactured from July to September 2014 and from July 2015 to September 2016.
Therefore, any D750 manufactured from July 2014 to September 2016 is eligible for inspection and repair of its shutter. Please follow the instructions in the “Identifying affected products” section below to check if your camera is affected.
We sincerely apologize for any inconvenience this issue may have caused.
Please direct inquiries regarding this issue to your nearest Nikon service center.
Thanks NikonRumors for spotting this!