In the past, I inadvertently secured my keys inside on several occasions. The initial occurrence was, oddly, directly outside the Bromley police station. I entered with a sheepish demeanour and provided an explanation. The man at the desk enquired about the make of the car. Austin A60. He provided me with a set of keys, stating, "One of these will fit." The initial one succeeded. Individuals exhibited a high degree of trust throughout that period.
I applied this knowledge when I performed the same procedure on my Bedford CA, which is also an FS series key. Feeling embarrassed, I enquired of a gentleman parked along the road if he would assist me by unlocking my van. I believed his key would be compatible. Indeed, that occurred. Neither vehicle was particularly valuable, although the A60 was stolen on one occasion. Parked it in the centre of Regent Street, left the headlights on, and depleted the battery. They clearly did not consider it worth retaining.