What it means is that, if the UFC are preparing the way for a new interim champion, then Jose Aldo would become featherweight champ again - automatically - and McGregor would be stripped of his belt.
So why has this happened?
Pettis, who once held the UFC and WEC lightweight titles, is looking to make his own mark by becoming only the fourth fighter (joining McGregor, Penn and Randy Couture) to win UFC championships in two weight classes.
The victor of the UFC 206 headliner is expected to fight Jose Aldo in 2017 in a title unification bout. McGregor (21-3) originally won the UFC's 145-pound title last December when he knocked out Jose Aldo in 13 seconds at UFC 194, but he never defended the belt. If the Irishman had his way, we all know he would continue his reign as the company's first two-weight champion until his eventual return in 2017.
Conor McGregor has been forced to vacate his featherweight title, UFC has confirmed.
The news comes just days after UFC 206's previous headliner, a light-heavyweight title rematch between current champion Daniel Cormier and Anthony Johnson fell through after DC suffered an injury.
Well, not only because in the past McGregor argued he could defend two titles, but because MMA Fighting's reporting sources have informed Ariel Helwani the Irish star didn't agree to relinquish the 145 belt.
Unfortunately for McGregor, he'll never get the chance to defend the crown he conquered Aldo for in 13 seconds a year ago.
UFC featherweight and lightweight champion Conor McGregor of Ireland attends the UFC Fight Night at the SSE Arena on November 19, 2016 in Belfast, Northern Ireland.
Aldo takes over as champion after winning the interim title against Frankie Edgar in July.
McGregor, 28, is expected to take time off from the Octagon to start the new season as he awaits the birth of his first child.
The 29-year-old Pettis (19-5-0) dropped to featherweight earlier this year submitting Charles Oliveira in his 145-pound debut after three straight losses at lightweight.
Also announced Saturday was a plan for Kelvin Gastelum to replace Rashad Evans in a middleweight bout against Tim Kennedy.