The Dungannon woman and fellow drugs mule Melissa Reid from Glasgow were reportedly told they could return to the UK imminently under new expulsion rules to clear crowded prisons.
Foreign inmates in Peru can apply for early release after serving a third of their term.
But the Sunday People reported yesterday that the pair must now wait months to hear when they can leave the notorious Ancon 2 prison in the desert north of Lima.
The delay reportedly comes after Peru's entire justice system ground to a halt last month when staff went on strike over pay.
Lima-based priest Sean Walsh said the women may now have to wait until at least February to get a transfer home.
"The strike could last two months - and with the usual month-long January holiday, they'll have to wait until at least February," he told the newspaper.
Michaella and Melissa were each jailed for six years and eight months in 2013.
They were caught with £1.5m worth of cocaine - hidden inside food packages in their luggage - on a flight from Lima to Madrid in 2011. Both initially claimed they were forced into the crime by drug cartel gunmen who threatened their families, but later pleaded guilty and received a reduced sentence. They completed a third of their terms last month and won permission to serve the remainder in the UK. Earlier this year it emerged that Michaella had become a beauty therapist in a bid to get early parole from her Peruvian jail cell.
In January her case was raised during a meeting of the Assembly.
Justice Minister David Ford then said they were awaiting agreement by the Peruvian authorities for repatriation.
"It is a matter of public record that an application has been made by Michaela McCollum which has been accepted within this jurisdiction but which has not yet been accepted in Peru," Mr Ford said at the time.