Acc to the map, the vacant adjoining lot is downslope. It appears to be the makeshift driveway that was encroaching on the adjoining lot.
It is unclear if this new buyer purchased both lots but likely he/she can find a plan which would include a sloped driveway next to the house on this lot.
It is unbelievable to me that an owner in this highly desirable urban area would attempt to steal up to a third of a vacant adjoining lot for ingress/egress in broad daylight and not expect repercussions!!