A number of teams had been looking for an alternative venue after Silverstone's test in July was reduced to two days, because they were not keen to run at Yas Marina in November.
An idea to run at Jerez post-season did not gather much support, but a proposal first put forward by Mercedes to test at Magny-Cours in the week after the Italian Grand Prix seemed more feasible.
Ferrari has now revealed that it is definitely attending the Magny-Cours test, with the Italian outfit also likely to be joined by Mercedes - although the Brackley-based outfit has not officially confirmed its plans yet.
Red Bull, Toro Rosso and McLaren are all sticking to their original plan to run at Yas Marina in the week after the Abu Dhabi Grand Prix - which takes place on November 4.
Williams, HRT and Marussia all elected to have their young driver test days at Silverstone.
Sauber, Lotus, Caterham and Force India's plans are not finalised yet, although it is possible that the latter may run at Magny-Cours too.