But it is believed Ferrari would prefer the 25th for the Maranello launch of its unnamed new car, as Enzo Ferrari always avoided running cars on Fridays for superstitious reasons.
Indeed, McLaren announced officially on Tuesday that it will launch its new car live on the internet on Friday, January 24.
Long-time title sponsor Vodafone has now departed the British team, which will be powered by works Honda engines from 2015.
It is rumoured Sony, the Japanese multinational, could become McLaren's new main backer, possibly complementing a new orange livery as the team prepares to put its Mercedes era in the past.
Official testing kicks off at Jerez a few days after the McLaren launch, and it is there in Spain that several teams, including Mercedes and Red Bull, will roll their 2014 cars onto the tarmac for the world's press.