Hello!
First, try to get the unaggregated data. But if that is not possible there is no differerence in handling preaggregated data and non aggregated data. Aggregated data is on another grain but business keys, relations an descriptive data can still be modeled. Do you have a sample of your pre aggregated data?
Good luck!
Is it clear what business concepts are represented in the aggregated data - it seems like calls per day per contact centre, so you’d have at least a contact centre hub. If it’s just contact centre, then I think you’d make a sat called something like sat_contactcentre_daily_call_total which has the relevant date in it. Are there other hub concepts there? If there’s more than one hub then you’d need a link and linksat.
These sound like JSON payloads, consider a satellite table with the JSON content in place but identify the business keys to have it hooked off a hub or a link table.