I'll preface this by saying the answer/instruction I got was not clear. They stated:
Oracle Cloud Email Delivery (OCI Email Delivery) uses a specific SPF include value. According to the official Oracle documentation (as of June 2024), the correct value to use in your SPF record is: include:rp.oracleemaildelivery.com . Use include:rp.oracleemaildelivery.com if you are sending email via Oracle Cloud Email Delivery (OCI Email Delivery).
_Use NetSuite’s SPF include (e.g., include:
_spf.netsuite.com) if you are sending email via NetSuite._
If you use both, you can combine them in your SPF record, e.g.:
_v=spf1 include:
rp.oracleemaildelivery.com include:
_spf.netsuite.com ~all_
Note the bold passage above. I do not actually know if we are using OCI Email delivery. BUT... when I tested emails to a Hotmail account, they showed like this screen capture (via
phx1.rp.oracleemaildelivery.com). Which I had never seen until our deliverability issues started abruptly. So I assuming my account is indeed sending via this OCI email delivery system. Being in another continent it's of course possible your emails are originating on a different system, but hopefully this helps.
If you think a ticket number is still necessary, let me know I'll give you that as well.