q re removal/recycling of WAL files

Let's say that there's a big update as part of a migration, and that update times out, and the migration utility retries it several times. (Context is that sequence happened through automated utility, and filled the disk, leading to an unfortunate series of events.)

1) At what point does WAL from the failed & rolled back operations "go away"? During the next checkpoint? During the checkpoint after completion of all other transactions which overlapped time-wise with the timing-out ones?

2) Is there a chance that never-visible rows would be written into tables, bloating them?

--
Scott Ribe
scott_ribe(at)elevated-dev(dot)com
https://www.linkedin.com/in/scottribe/