https://i.imgur.com/M40giWE.png

The green inner circle is the max range I can move a combinator using Dollies. The red circle is the max range I can connect two combinators. This is with no other mods installed.

The range you can connect combinators is about 1 higher than the range that Dollies lets you move combinators.

Can I be lazy and request a save file with this setup to test.
I will try and get to it this weekend

Here's a blueprint with a circuit connection and dollies refuses to move the entities closer because 1 space closer is still greater than dollies' max circuit range

0eNqVktFugzAMRf/Fz6EqVYEO7U+mCQVwmTVwUBKqoSr/PodMXaX2YeMhwsa+9+D4Cu244GyJPdRXoM6wg/rtCo4G1mPM+XVGqIE8TqCA9RQj543VA2Ze8ycEBcQ9fkGdh3cFyJ48YdLZgrXhZWrRSsFzBQWzcdJkODqKUHYoq12hYJXX/LTfFeLRk8Uu1RwUCCmn0MWePB4W+3tT6lMl2W4hv4UCGEJQD1yHG1ePHfVos85MLbEWymd0xR1dHjYab83YtPihLyQ9Uvij1Mi3nm6gZ7LONw/jvZD1i2R+57NVZHhBu/oP4gGSjZOByV3l+/jEzDRru2HW8CrtZvHz8g+DwSJy0p5XYV3YN2drpoZYdKA+69FhCH8eeJqwrMG2MPXdfimQf3Hp/k75sTq+VGWV78uiDOEbbhLbcw==

Ok. Not sure what to do with this because..... everything is correct according to logic.

Copper max is 9 and circuit Max is 9.....
Pole to pole only goes 9 tiles. As expected..... but pole to circuit goes 10...... even though the max is 9 in the prototype

I need to test circuit to circuit stuff and see what happens yet.

My guess is this might be a wont fix factorio bug but I need to dig into it deeper and possibly figure out some sort of circuit network hack for it.

Good News, I think I figured it out. Copper wires are made of a metal like material, and circuit wires are made of a stretchy type material and I should have a release soon.