Not the same servos.
Last time they changed a few and decided to change them all this time.

 

Yes, the dash has to be removed for the replacement. When the dealer did mine on my IS350 they ended scratching my steering wheel and the inside drivers door panel which eventually ended up tearing some time later from heat stress. The material was synthetic Nuluxe. After I got my GS I decided to use another dealer. This issue, stuck vent mode, happened on my GS. On my next service visit, I mentioned it to the service advisor. The problem was addressed when they returned the car. However, when I enquired what addressed it, they said they did not find any issues. They must have “reset” the servos. Now I am careful to just leave it on the mode I like. I wonder if this is addressed on the newer cars such as the LC.