Late Polyclar / silica addition?

Given a firm bottling deadline, when is the latest one should add silica gel or Polyclar to a secondary fermenter before they should consider just not adding it at all? Is 24 hours enough time for these fining agents to work and settle out? It seems that if either takes multiple days to precipitate out of solution, then perhaps one without that kind of time is better off with a potentially cloudy beer than a product that has plastic still in suspension.

Throw the PVPP into the carboy and rack when clear. You can consume some without ill effects.

To each their own. I’d drink it cloudy or allow it to clear naturally, but I only use irish moss/whirlfloc in the boil.