Substitution Variable in Member Formula Needs Refresh?

Summary:

We have observed that a member formula with a substitution variable does not use the current value of the variable but rather is using the value of the variable when the database was last refreshed.

Content (required):

Our expectation is that a member formula will use the current values of substitution variables when they accounts are retrieved. But if a variable value is changed, the member formula is not using the new value until the database is refreshed. Has anyone seen this? Is our expectation correct?

Version (include the version you are using, if applicable):

21.10.84 and 21.11.70

Code Snippet (add any code snippets that support your topic, if applicable):