There is only one moment when the drop is singular, otherwise it has no idea what a drop is...it is One thing that is all expansive...it is Singular.
Well, what happens when the whole ocean is split up into singular drops? Then they all fall back together to reform the ocean.
I don't think there is such a thing as a final moment...well, there is for a Singular thing that has expression and existence, but all things die and revert back to their component parts which is mainly pure energy that accumulates matter about it. The ocean is pure energy.