The board is showing the wrong order

The board is not sorted by when a job arrived. It is sorted by when it is due.

The rule

Within each status group, jobs sort by promised date, soonest first. Two jobs promised the same day sort by how long they have been waiting, oldest first.

So if something looks out of place

Check its promised date. A job with no date sorts to the bottom of its group, which is usually what people are seeing when they say something has "disappeared".

Priority

Marking a job Priority floats it to the top of its group regardless of date. Use it sparingly; a board where a third of the jobs are priority is a board sorted by nothing.

Still here

Still here is the exception: it sorts by age alone, oldest first, because the only question that view answers is what has been sitting here longest.