Nope, don't worry. Not everyone gets that and eCAS is notoriously inaccurate. The sponsor's side has shown "in process" for me since I got AOR and I don't think they started processing it until last week (I received an email from CPC-M in response to my emailing them about a mistake on my application).
Does the sponsor live in England? If you log in with the sponsor's information and the UCI from AOR it shows the sponsor's home address, not necessarily the principal applicant's.
Oh, and I don't know if it's worth noting, but I got that email from CPC-M at 4pm PST (3 days ago).