Emails back to showing via phx1.rp.oraclemaildelivery.com

Starting on Wednesday we have noticed that our emails coming from netsuite are back to showing via phx1.rp.orqclemaildelivery.com yet nothing has changed on our end with the spf or dkim. We were fine for over a year but now back to this. Customer service says nothing changed in their end so not sure where to go from here. Anyone else experiencing this?