Pity the photos on e-bay are so indifferent Clint
I do agree, it has to be 216 Sq even if the date of March 1918 is a bit early.
The unit didn't arrive into France until 30 March 1918 and that was into Villeseneaux. They didn't move into Ochey until May.
I also believe the final photo is from 216 Sq. If the same aircraft, I don't know since the unit had A-1, B-3 as well, so it seems they were coded with both letters and digits, perhaps forming four flights (A-D) and possibly having three aircraft in each flight, A-1 to A-3 etc. So this one could thus be anything from D-1 to D-3, if my conjectures are correct.
The serial numbers are all well hidden on the rear of the fuselage, being excellently (
) hidden by the fins....
Cheers
Stig