Well, those aren’t secured at all, so the possible grate system above might be a better solution.
While that thwart board holds that last rank of jugs upright, we have to keep in mind that it’s only a display cross section indicating hull construction primarily.
There are some interesting under water videos of the Kyrenia wreck that show the large number of jugs tightly clustered and toppled over? Worth a few minutes. I”ve put off searching for the full size sailing replicas of the Kryenia ship for later.