As McLaren set the car up for first practice, they appear to have new pod wings complete with mirrors. This is an aerodynamically benefical location for the mirror, McLAren have been late to try this set up out. Drivers do say the rearwards visibility is compromised, although there is a FIA static test for the quality of the drivers rear view. Both types of mirrors are mounted with infrared tyre temperature cameras, so we can expect to see the team to alternate between the options in free practice.
Scarbsf1's Blog 
Scarbs,
Why did the FIA ask McLaren to remove their new wingmirrors for qualifing? It seemed to me that the wing mirror upgrade added a tenth or two and dont understand why they have made the team remove them…
Thanks, Ross
I asked the team and… “We made a decision after P3 to remove them. Not sure yet if they’ll be making a comeback – just another one of those aero tweaks that was worth investigating!”
Is there a limit or regulation as to how many mirrors a car can run with?
I dont think there is a limit, they set a minimum area and position from the cockpit, but as far as quantity I guess thats free. McLaren did run with two pairs a few years ago and tried a pair of mirror pods with three seperate mirror glasses on the MP4-17, the ideas didnt catch on.
I see,wouldnt be surprised to see some sort of casing shape kept on the side pods and the mirrors at the cockpit.
I’m sure the teams would like to, but the sidepods height is limited in the bodywork rules. The mirror housing was an exception to this height rule. With no mirror inside, the housing would not be permissible.
One of the benefits of the pod wing mounted mirrors, was that although the housing was a pretty unaerodynamic shape, the housing could still be used in a limited way to divert the wake of the front wheel away from the car.
Im sure the teams will adapt,iv never heard of a car being uncompetitive because the mirrors were in the wrong place.