Reading the AD7767 data sheet Absolute Maximum Ratings, it appears that it is possible to have power on the VDRIVE pin, but none on the AVdd, DVdd and Vref.
Is this correct?
I am designing a board where it may be that during initial programming, there will be only the digital supply (VDRIVE), but no analog supplies (AVdd, DVdd, Vref)
You are correct. During initialization it is normal for the supply rails and reference to be brought up in a different sequence. As long as you adhere to the Absolute Maximum Ratings the device will operate as expected without fear of damage to the device.