Acceleration does not mean every space number goes up

In the expanding universe, acceleration means the expansion itself is speeding up. But that does not automatically mean the Hubble parameter is increasing.

Accelerating Expansion of the Universe

Here is the strange part

For one particular distant galaxy, its recession speed can rise over time as space expands. But the speed-per-distance measure can still go down, so galaxies crossing a fixed boundary do so more slowly later on.

Accelerating Expansion of the Universe