Polish revolt of 1905 succeeds

[WolfBear]

Do a search for a map showing railroads - and Russian gubernia borders - in the area. That will answer your question.

There appears to be a path from Kovno and another one from Bialystok:

 

[WolfBear]

This is somewhat off-topic, but I find it interesting that the heavily densely populated Polish and Ukrainian parts of the Russian Empire were cut off from each other by Austria and by somewhat less densely populated territories:

This would mean that in order to have any chance of success in a pre-WWI/no-WWI world, a Ukrainian independence rebellion would need to at the very least also have Austro-Hungarian support, not just Polish support.