t2u oracled seems not to reuse worker numbers (slot numbers)

I notice that currently the manager web page reports worker with ident tag2upload-builder-01.debian.org,1384867,w11.

And on tag2upload-oracle-01, /srv/oracle.tag2upload.debian.org/home/worker-cwd/ contains diretories w0 to w11 inclusive.

This isn't quite entirely cosmetic - the cwd reuse is a (small) waste of space.

If you don't want to investigate this please just assign the ticket back to me...