This can be adjusted out by loosening the bushing holders from the bed plate and turning them so that they stay in contact with the y-rods while traveling.
I too have the same amount of slop in the bushings, not sure if it’s a bad batch or meant to have that much, but it made my carriage move up-down about 0.5mm when changed X direction. I tightened it up following Caleb’s directions but it won’t be perfect.
I picked up replacement bearings for ~$1.20USD on fleabay, cheaper than the bushings so I’m hoping they are not total garbage. If they hold up and eliminate the ~1mm slop without misalignment, I’ll deal with a slightly louder machine any day.