Hi CWDdkops,
Yes, you are right.
Rollup fields are calculated by scheduled system jobs that run asynchronously in the background. The jobs can be viewed and managed by an administrator. There are two types of system jobs:
(1) Mass Calculate Rollup Field job that runs once per rollup field 12 hours after you created or updated a rollup field.
If you don't want to wait 12 hours, you can go Settings > System Jobs to find Mass Calculate Rollup Field job for the new craeted rollup field to Resume it.
(Dynamic CRM follows specific naming convention for Rollup Jobs.EntityName.FieldName)
(2) Calculate Rollup Field job that runs per entity and recalculates all rollup fields for that entity by processing the records that were created, updated or deleted since the last recalculation. The default maximum recurrence setting is one hour.
If you want to modify recurrence, you need find Calculate Rollup Field job for current entity.
Changing the recurrence is supported only at entity level and not on single field. So, opening the Calculate Rollup Field Job will give me this.
Also, It is possible to manually recalculate individual rollup fields by choosing the Refresh icon next to the rollup field on the entity form. User must have write access to the record on which refresh is requested.
For more details, you can refer following link:
Create rollup fields in Dynamics 365 Customer Engagement (on-premises) | Microsoft Docs
