You have eloquently stated what capitalism and private enterprise are about, eg profits. While many [conservatives] rail loudly about 'red tape' impeding business the purpose of that 'red tape' is usually to overlay integrity and public responsibility into activities where it otherwise would not exist.
Yet many people continue to vote in favour of less 'red tape', less government, and more private enterprise, but bleat when the reality sets in that capitalism is for the benefit of capitalists not of 'the public' unless 'the public' is congruent with 'their customers'. When the latter holds, the common outcome is to charge the most and deliver the least, also referred to as 'what the market will bear pricing' to maximise profits and thus dividends and thus support a high share price, noting executive options are part of their compensation and are favourably taxed as capital gains events -- eg the executives have a vested interest in pumping up the share price any way they can.
One need only survey the societal outcomes of the many 'public-private' partnerships across Australia that mostly privatise profits and socialise losses. Since Medibank Private had its IPO the beneficiaries appear to be the shareholders and executives in 2016 and more in 1H2017, rather than their policy holders (customers).
In the case of health funds there is anecdotal evidence that Medibank, as an historic market maker, will be a leader for customers' costs while delivering as little as possible in return, and the competitors take the cue and follow along. All the while government constrains Medicare to make a 'vibrant and profitable' capitalistic health insurance industry - eg follow the money.
Health funds are insurance companies and can be expected to work chapter and verse to a policy as it is at the time. Only Medibank can answer that question, and get it in writing (or email) as that usually encourages a more rigorous response as they can be held accountable more easily.