I'll have to do some testing and get back to you. These steps were derived from my AV1 encode process, minus the re-encoding. I'll try doing a true replication of this process.
Jellyfin 10.10.1 (Docker)
Ubuntu 24.04 LTS
Intel i3 12100
Intel Arc A380
OS drive - SK Hynix P41 1TB
Storage
3x WD Red Pro 6TB CMR in RAIDZ1 (JF Library)