Michaela McCollum and Melissa Reid are both expected to plead not guilty at a preliminary hearing in Peru next week.
The two women are likely to face several charges after they were found with €1.7 million worth of cocaine at Lima airport last week.
Local legal experts say if the girls cooperate and provide assistance in other investigations they could shave up to two years off any sentences they are given, if found guilty.
Michaela expects to meet with her Belfast solicitor Peter Madden when he arrives in Lima later.
Daily Mirror journalist Christopher Bucktin, who has been speaking to the women, says Melissa's day will be a little different: