I don’t think there is a Public REST endpoint that can fetch all of them consolidated.
Even the IDN is using some internal API endpoints to make the updates like,
If you are looking for some temporary hacks maybe you can consume these internal APIs to write a simple script that can pull out the details you are expecting in loop.
https://<tenant_id>.api.identitynow.com/diana/sources/sources/<source_id>/accountAggregationSchedules
https://<tenant_id>.api.identitynow.com/diana/sources/sources/<source_id>/entitlementAggregationSchedules
To get more information related to this open your devtools in browser and monitor the API call made to load that data in the page. Use AggreagtionSchedules as filter and you should see the API calls in the network tab.
Note: This above endpoint may work only with the Auth token based on the browser based login and may not work with the PAT token. [Quick read]
Per my understanding, I don’t think we can get this information from Search API too