Three Westcountry hospitals have revealed delays – in one cases amounting to several years – in crucial bids to go it alone.
All NHS trusts must achieve coveted Foundation Trust (FT) status or face the prospect of being taken over.
However, Plymouth Hospitals and Northern Devon Healthcare have both admitted they are lagging behind their initial plans.
Meanwhile, the Royal Cornwall Hospital, which is the furthest forward of the trio, recently asked for a "pause" in the process.
Bosses at Plymouth's Derriford Hospital had planned to have their application on the table last autumn and for it to be approved by now.
However, Lee Budge, director of governance, said there were hurdles to overcome and the bid may not actually be submitted before early 2016.
He said: "We face a number of challenges before we can move to becoming a Foundation Trust with absolute confidence."
Mr Budge added: "We absolutely expect to be in a position to make a standalone FT application by the end of 2015/16."
In the meantime, he said Derriford was working with the NHS Trust Development Authority (TDA), which supports trusts on their route to FT status, "to ensure we have long-term sustainable plans."
At Northern Devon Healthcare, it had been hoped to submit the application to the Department of Health 12 months ago, which would have then been assessed for soundness by Monitor, the independent regulator.
However, it has yet to hand over its business plan to the TDA, though this is scheduled for July with a formal FT application hoped for this Autumn.
Jac Kelly, the trust's chief executive, said: "The timetables for both the TDA and Monitor are out of our control but we are confident we will gain authorisation early next year.
"Given the volume of trusts seeking to go through these stages over the next 12 months, there is naturally a risk of delay."
There are currently 146 FTs in England, including South Devon Healthcare in Torbay and the Royal Devon and Exeter Hospital, which was among the first to win the status bringing greater independence from Whitehall.
Of the 101 remaining, Royal Cornwall Hospital is in a small group whose application is at the final stage of being scrutinised by Monitor.
The Truro-based trust initially expected to tender its application in January last year, although it actually submitted in October,
At a meeting with Monitor last month, it requested a "pause" in the process to gather more information.
However, chief executive Lezli Boswell, said they would achieve their goal of gaining FT status this financial year.
"RCHT has made excellent progress in the past 12 months and we remain on track to become an NHS Foundation Trust in the financial year 2013/14," she said.
At its board meeting last week, the TDA was told that despite "significant focus" in recent years, the rate of progress in achieving FT had "slowed."
