It's my understanding that the notification process, in and of itself, is not a particularly lengthy or onerous process. Presumably, there is a meeting of the sanitary and phytosanitary committee, at which time they might table their change. The greater time constraint, or time requirement, is the domestic gazetting process in India once they've filed with the WTO. That, I believe, is a two-month process.
On April 6th, 2017. See this statement in context.