Sendinblue is a third party sender based in France:

Aligned Authentication method:

SPF - Yes - Only if the customer has a dedicated IP

DKIM - Yes TXT record

With a dedicated IP, the customer will configure a dedicated subdomain for Sendinblue. This can either be hosted on the customer’s DNS or the subdomain can be delegated to Sendinblue.

Sendinblue has a verification process that checks to see if a customer has correctly published SPF and DKIM records before they will send in an aligned way. This check is only done when Sendinblue is being onboarded to a domain that is already pointing SPF to Valimail and not when Sendinblue was already configured as a sender in the customer's DNS before pointing SPF to Valimail. 

Sendinblue does a simple text match for their SPF include and is not able to recognize the  Valimail Macros. In order to bypass this, the SPF include for Sendinblue needs to be temporarily added after the Valimail Macro, the record now showing like this: 

v=spf1 include:%{i}._ip.%{h}._ehlo.%{d} include ~all

The Sendinblue include can safely be removed once we make sure that the emails are being DKIM signed and that they have verified their include exists. 

More information is available here: