The observer is now in point t on its trajectory. Time t is a time that passed from BigBang - in other words it is age of the Universe.
The space dimensions are different for each observed galaxy (they are perendicular to the trajectories of the observed galaxies).
The direction in the FER interpreted as the space dimension for galaxy that moves along the red trajectory is drawn red and the same for the green trajectory
The observed velocites of galaxies are then equal to:
t - age of the Universe
H - the Hubble's constant
The observed velocities of galaxies are proportional to the observed distances from the galaxies
The factor of proportionality -the Hubble's constant - equals to the inverse of the age of the Universe and is decreasing with the time flow.
The increase of velocities of galaxies is only an effect of the way in which we perform the observations.
It has nothing to do with any actual acceleration.