I speculated late last year that Bp Lopes, having taken over the OCSP after Msgr Steenson's removal a year before, was acting as though he would be held accountable for the OCSP's performance on the anniversary. A glossy soft-focus brochure was put out to celebrate his achievements. Effort has clearly been made to create the appearance of new groups coming in. Problems like the inability to implement financial software or conduct a parish census are pushed into the shadows. Financial shortfalls, dire as they may be, are minimized.
Msgr Steenson and the key people around him were removed pretty clearly for unsatisfactory performance. This suggests that there were expectations in the CDF that things should have turned out better than they had. In the corporate accountability paradigm, which may apply here at least in part, if A doesn't perform, A-prime, his superior, is held accountable. If A-prime can't fix the problem caused by A, then A-double-prime, his superior, will hold him accountable.
In this reasoning, Bp Lopes was sent in to fix things in the new division, which Msgr Steenson had been unable to do. I suspect that someone in headquarters has been taking a close look at sales and revenue. But A hasn't done any better than his predecessor, as far as headquarters can see. So the ax falls on Cardinal Müller, who is A-prime. (Keep in mind that the six unnecessary months spent sorting things out for Our Lady of the Atonement was 10% of Cardinal Müller's tenure as Prefect of the CDF.) A corporate VP who was this feckless would in fact be let go.
In this model, which may or may not apply, we may surmise that the OCSP has been under major scrutiny. If true, resolving the OCSP issue will be near the top of Abp Ladaria's to-do list. In that case, we can expect further changes.