I sent an enquiry to London as to why my SA approval still hasn't changed in Ecas. Whilst I was at it I also asked about this new ' in processing' protocol. They replied today and they actually answered me. Unfortuently, it's just like we all thought. Nothing to get excited over, they aren't suddenly looking at 3 month old applications. It literally just means that they have recieved it. Not that it's been assigned am officer, not that they have opened my application.
Official reply below
With regards to your application status in ECAS indicating it is in process, this means that your application has been transferred the visa office that will be processing your application. In your case, this is the London, UK office. However, your application has not yet entered active processing (been assigned to an officer) at the London visa office. Applications are processed in the ordered they were received at our Case Processing Centre – Mississauga. We are currently processing applications that were received at CPC-Mississauga in December 2014/January 2015. Once applications are assigned to an officer, our aim is to finalise the application within 8-12 months. Unfortunately, we are unable to provide you with an estimated time as to when your application may be assigned to an officer.
The fact it could take 8 - 12 months after they assign an officer is worrying. If they are working on Dec/ January then they are running at around 8-9 months before they give the file to an officer to add to their pile of applications to look at. From what they are saying it could take another 8-12 months for for them to actually look at it and make a decision! Urgh. Hopefully the officers start speeding up how long it takes them to open and finish a case.