Start Event - Time recurrence

Agree with Mike, I believe that input is looking for an integer value only.

Additionally, instead of the XOR method we can also used the Advanced Timer Conditions, still set the process to attempt to start every 1 month, then add a condition which will stop the process from firing unless the current month is in your list:

contains({1,4,7,10},month(today()))

This approach is cleaner, though I can never quite get over how much harder to actively test it is.  With the "XOR method" you merely launch an instance whenever and watch it bomb out.

Mike Schmitt said:

This approach is cleaner, though I can never quite get over how much harder to actively test it is.  With the "XOR method" you merely launch an instance whenever and watch it bomb out.

You just have to have faith sir

I do agree on, liking to be able to actively test everything.  For these, I'll typically make a non-prod expression rule to run test cases on my timer condition, then make reminders to verify on test servers/production at those times for the first set of runs to ensure all goes well.  I like to avoid extra starts in general as a habit.  I do still have a few that use the XOR method, it is low overhead especially if you have a parent process which only handles the Start->XOR->End OR Start Process for your main PM.

6 of 1, index() of property()

Mike Schmitt said:

This approach is cleaner, though I can never quite get over how much harder to actively test it is.  With the "XOR method" you merely launch an instance whenever and watch it bomb out.

You just have to have faith sir

I do agree on, liking to be able to actively test everything.  For these, I'll typically make a non-prod expression rule to run test cases on my timer condition, then make reminders to verify on test servers/production at those times for the first set of runs to ensure all goes well.  I like to avoid extra starts in general as a habit.  I do still have a few that use the XOR method, it is low overhead especially if you have a parent process which only handles the Start->XOR->End OR Start Process for your main PM.

6 of 1, index() of property()