Log backups are important for point in time recovery and to automatically truncate the log file (in full recovery model) to make space for log reuse.
But when the secondary is unreachable either due to network issue or post failover, then I'm learning that log keep growing (because it prevents truncation: https://www.sqlshack.com/sql-server-transaction-log-growth-monitoring-and-management/).
In this scenario, log backup won't truncate the logs, so does that mean the log backups that occur behave like copy only log backups? That is - log backups won't truncate the logs (so each subsequent log backup size keeps growing) and yet it also allow for point in time recovery.
Is that a correct understanding on the log backup behaviour?