FunBike31I ended up downloading the a12 update from the website.
The updates are distributed by group so as not to saturate, but your delay seems indeed very long.
OTA updates can be blocked
-By the editor for x reasons
-By unlocking the bootloader, by rooting the device
-The unlocking of the Bootloader is registered with Asus, even by reblocking it the OTAs remain blocked. Same with hiding the Root or deleting it.
this is the case for example of the Chinese rog delivered with a WW firmware
-May be an impossibility of the A11 updates due to the distribution of A12, it seems most likely to me, in this case, you must download the firmware from ASUS and save it to the Root of the phone, it will be done when the phone is restarted 'device.
this solution is better than the OTA, if you turn off and turn on your device before downloading you are sure to be in the best system conditions