AFAIK, Google has a very similar policy. At FB, E5 is a "terminal level", so once you hit that level, there's no push or expectation to reach beyond that. I've been in the E4 red zone at one point, and spent about a year getting evaluated at E5 levels before getting the promo. You're not automatically out if you don't reach it in time, but you have to be showing progress, and it does get more urgent the longer you spend in that zone.