Thick Band on K20D Images

Has anyone come across a thick band on images? I did a studio shoot yesterday, and a small number have got a thick band on them. The camea has only recently come back from repair (sensor)

Thoughts?link

Tried the link and it says the page is private

Whoops

try this one

link

It looks similar to the problem Prieni had.
https://www.pentaxuser.com/forum/topic/K20D-vertical-banding-8841/p-0

I did look at that thread, but it appears mine is a thick band rather than lots of small bands.