See also #6376 #6380. I have some changes that turn the paragraph in [atomics.order] into recommended practice.

An implementation should ensure that the last value (in modification order) assigned by an atomic or synchronization operation will become visible to all other threads in a finite period of time.

- [intro.progress] p18

Implementations should make atomic stores visible to atomic loads within a reasonable amount of time.

- [atomics.order] p10

Firstly, both of these paragraphs should be formatted as recommended practice. Secondly, there is such significant overlap that it may be worth coalescing them into one.