From Sony Asia:
Thank you for using Sony products.
It has come to our attention that the following issues may occur with our a7R III and a7 III interchangeable lens digital cameras.
Notes:
We will provide an update to the system software addressing to the above issues in mid-December. Until then, please take the following precautions:
While we are preparing to provide new system software, we will no longer offer updates to the current system software.
We would like to apologize for any inconvenience caused while using the affected products and thank you for your understanding.
Thank you for your interest in Sony products.
In certain shooting conditions an out of focus issue may occur with some 24-105mm F4 Full-frame E-mount G (SEL24105G) lenses.
To address this issue, subject to the terms and conditions in the Limited Warranty that accompanied the Affected Lens, we will repair your Affected Lens, free of charge, through March 31, 2020.
We apologize for any inconvenience this may cause, and thank you for your understanding and cooperation.
Symptoms
These symptoms may occur under certain shooting conditions:
Check Whether or Not Your Lens is Affected
This only applies to SEL24105G lenses with certain serial numbers.
The SEL24105G serial number is on the side of the lens near the base.
To see if your lens is affected type your serial number in the box on this website, and then click the Check Serial button.
If you have further questions, please contact Product Support for assistance.