I have split my automations using:
automation manual: !include_dir_merge_list automation/
in my config file and put all my automations in folders within the automation folder.
I created a new automation using yaml in one of the folders in automation…and I made an error which was caught when I reloaded my automations using configuration->server control>YAML Configuration loading.
I then corrected the error, cleared the error notification and reloaded the automations again…but I was still notified of the error…which had been fixed.
I then restarted Home Assistant and no error was found.
Apparently, reloading automations does not correctly handle changes to automations in split automations correctly.