On 22 June 2022 at 10 UTC the AA complex became unavailable for essential hardware and software upgrades. In preparation for it, the complex was drained and jobs due to finish after 22 June 2022 at 10 UTC did not run. Those jobs still running on the system at the time would have been killed. You may continue to use the AB complex for your interactive and batch workloads.
We strongly recommend all users to use the new generic hostnames for our Atos HPCF service instead of the specific complex login nodes. You may use hpc-login for interactive login access and hpc-batch for remote batch submission, which will always point to an available complex
Note that the shorthand hostnames such as aa.ecmwf.int have also been retired in favour of the alternatives described in HPC2020: How to connect.
You have more information on how to connect to the Atos HCPF in the HPCF Documentation pages.