This paper examines the linguistic and social factors constraining the variable use of expletive il in Montréal French. Based on two corpora of spoken French recorded in 1971 and 2012, we study the evolution of the omission of il over 40 years. The analysis of the linguistic factors shows a general omission increase between 1971 and 2012, but within a stable language system, as this variable is subject to the same linguistic constraints despite the passage of time. However, while the general tendencies suggest that the omission is on the rise in the Montréal community, the apparent-time analysis of the 2012 data shows a reversal of this trend toward the standard variant (il realization).