The tank in the last photo is a Mark I Challenger, I believe. The profile is a bit "odd" because at that point the Battle Group was conducting a "withdrawal under fire" ..... thus, although the tank was moving at speed (to the left) the turret was rotated so the gun was trained backward.
I actually posted the three photos in jumbled chronological order ....
The middle photo is of one of the self-propelled guns which actually withdrew first, well in advance of the tanks to a position several miles to the rear in order to cover the withdrawal. Once the guns were positioned, the tanks began coming over the horizon in their withdrawal, moving through a narrow gap in a "minefield" right below our observation post, and then continuing past us (like the tank in the lowest photo). Once the tanks were through, a swarm of Royal Engineers completed placing and detonating charges which blew a very substantial tank trap across the gap, supplemented by more mines for good measure. All that while we could hear the rumble of the artillery firing well to our rear, plus the whistle of their rounds passing over our location and then exploding beyond the horizon ....
The observation party I was with were then moved back to a "middle ground" position where the tanks were again deployed to cover the further withdrawal of the artillery to the final defensive position. We were quite close to the tanks at this location as they began to engage the advancing enemy - consisting of pop-up tank silhouettes which registered hits by the non-explosive rounds the British tanks were using. Due to the very dry conditions, the tanks would virtually disappear in a cloud of dust kicked up by the muzzle blast of each round fired.
We then moved back to that final defensive position on the far side of a "river" (entirely imaginary, as you could probably surmise from the nature of the terrain!
) The British tanks and infantry withdrew across a trestle bridge which the Engineers were busy rigging with explosives .... then, when the forces were all across and clear, they blew the bridge. The final picture chronologically (albeit the uppermost one posted above) shows one of the tanks firing from a "hull down" defensive position at that "last stand" location.
Needless to say, I took other photos that day, but am currently unable to locate them!