Firstly is there an infinite set of compressions that a point in space time can be at? My answer is yes.

Secondly if you plot three dimensional space x y z and then you expand the distances between the points, although the relative proportions of x,y,z hold. The distance changes. now lets say that we have a two dimensional space and we double the space. We draw the first graph on one sheet of paper and the doubled graph on a second. we gave the first graph an arbitrary value of one and the second graph a value of 2x1. We could then create a 3 dimensional space where the at point 1 of depth ( dont want to use z here so not to confuse it with the spatial dimension of z ), we have a point or a line or curve or whatever and at point 2 of depth we have each point, curve or line at proportionately double their x and y values. Now we fill in the spaces between with straight lines. We can then define the difference between point a at a compression of 1 and point 1 at a compression of 1, in fact point a ( in 2 dimensional space ) is represented in three dimensional space. I can then give you a distance of 1 between point a of compression level 1 and point 2 of compression level 2. What would the units be?
Actually I think we can draw a 2 dimensional space with a certain contraction factor to represent 3d sapce. This would be like a real picture. Kind of like a holgraph.

Now we switch from 2 dimension to 4 and add the one of compression and we have 5. We can now tell the difference between a light year at compression 1 and a light year at double the compression of 1. As t changes. the compression for each point relative to inself change would stay at 1 ( or 0 ). so at 1 second you would have a relative compression of 1 and if you moved you would have x', y', z', t' looking at it from one point over at a specific place in time you would have x + delta x, y, z, c' , 0 so at a certain point of time there would be a difference in compression for every point in the universe relative to us.