During a release we track the status of testing images as we go. This is coordinated in IRC on irc.debian.org #debian-cd.
Link to the test pages should be added here:
Bookworm (Debian 12)
2024-08-31 12.7
2024-06-29 12.6
2024-02-10 12.5
2023-12-10 12.4
2023-12-09 12.3 This release did not complete
2023-10-07 12.2
2023-07-22 12.1
2023-06-10 12.0
2023-04-01 Bookworm d-i RC 1
2023-02-18 Bookworm d-i Alpha 2
2022-09-20 Bookworm d-i Alpha 1
Bullseye (Debian 11)
2024-08-31 11.11
2024-06-29 11.10
2024-02-10 11.9
2023-10-07 11.8
2023-04-29 11.7
2022-12-17 11.6
2022-09-10 11.5
2022-07-09 11.4
2022-03-26 11.3
2021-12-18 11.2
2021-10-09 11.1
2021-08-14 11.0
2021-07-31 Bullseye d-i RC3
2021-06-09 Bullseye d-i RC2
Buster (Debian 10)
2022-09-10 10.13
2022-03-26 10.12
2021-10-09 10.11
2021-06-19 10.10
2021-03-27 10.9
2021-02-06 10.8
2020-12-05 10.7
2020-09-26 10.6
2020-08-01 10.5
2020-05-09 10.4
2020-02-08 10.3
2019-11-16 10.2
2019-09-07 10.1
2019-07-06 10.0
Stretch (Debian 9)
2020-07-18 9.13
2020-02-09 9.12
2019-09-08 9.11
2019-09-07 9.10
2019-04-27 9.9
2019-02-16 9.8
2018-11-10 9.6
2018-07-14 9.5
2018-03-10 9.4
2017-12-09 9.3
2017-10-07 9.2
2017-07-22 9.1
2017-06-17 9.0
Jessie (Debian 8)
2018-06-23 8.11
2017-12-09 8.10
2017-07-23 8.9
2016-06-04 8.5
2016-04-03 8.4
2015-09-05 8.2
2015-06-06 8.1
2015-04-25 8.0
Wheezy (Debian 7)
Squeeze (Debian 6)
2011-02-09 6.0