How does phosphorus cycle restart?
As far as we know, the phosphorous cycle has gone on since the early oceans and atmosphere eformed, some 4.0 billion years or so.
The phosphorous cycle has probably gone on for about 4 billion years and started shortly after the oceans and atmosphere formed. It may have accelerated when life really got going about 500 million years ago and then again about 350 million years ago when land plants evolved on the land. Human activities in recent decades have dramatically accelerated the phosphorus cycle, by the use of fertilizers and grazing animals.
There was a time in the pre-Cambrian era, about 700 million years ago, when the entire Earth froze over and it is possible that the phosphorous cycle slowed down or perhaps shut-down at that time. But it would have re-started naturally once this cold spell was over.