The Caravelle has two wing fences on each wing, so as to limit the spanwise airflow (and associated tip-stall problems) that would otherwise occur due to its rearward-swept wings.
On most Caravelles, such as this VI-R, this takes the form of a large inboard fence which wraps around the leading edge of the wing, and a smaller outboard fence which starts significantly behind the leading edge and rises only about half as far from the wing's surface as the inboard fence does:
On most 10Bs and all 12s, in contrast, the outboard fence is larger (although still not quite as large as the inboard fence) and wraps around the leading edge in the same manner as the inboard fence, as can be seen on this 10B:
However, some 10Bs, such as this one, have the older, smaller design of outboard fence:
Why the two different styles of outboard Caravelle wing fences? I'm wondering if it might be related to the modified wing used on the 10B and 12, but, if so, then why do some 10Bs have the older style of outboard fence?