If there is ever a need to run a SQL Server job on an adhoc basis outside of its normal schedule, don’t change its original schedule. Rather, create a new one-time only schedule for that job and leave it like that even after the the execution.

If you modify the original schedule then you’d have to remember to revert it back. This can be easily missed out and then the job would be running at the modified schedule after that! Oh, so you say you have a water-tight reminder mechanism and you’ll never forget to revert it?! Please read the next line.

If there was a requirement to run the job out-of-schedule once, then it could happen again too. The one-time schedule would be handy at that time and can be reused.