Yes, a communication would be great (including, on this thread).
As it stands right now, the linktargets table is incomplete on the wikis I checked. For instance,
this fawiki query returns 388 results but the
equivalent query using linktargets only returns 4 results.
For some update, on the
s7 run is now backfilling eswiki which comes right before fawiki. Once that's over (in a couple of days at most) it'll start backfilling fawiki. The rows you're seeing are due to write both (new pages, new edits, etc.). But this is already backfilled in many wikis, for example frwiki, arwiki, etc.
My bots are using quite a few queries that rely on pl_title or pl_namespace. I'd rather spend time update the queries only after the linktargets table is fully updated, so I can compare the results of old and new queries as a validation step.
I will inform you once the fawiki run is finished.
Amir,
To summarize: the only wiki that will soon get the old columns dropped is commonswiki and the rest of the wikis will keep the old columns until the migration to the new columns is complete on all wikis, at which time there will be a communication.
Is this correct?
Yes, until further communication, only s4 (commonswiki and testcommonswiki) and testwiki (s3) will have their old columns removed.