Is there anything blocking you from upgrading only your unit's connection?
You'd generally need a permission from other owners for any work in the hallways and such, but as long as the disruption is not too bad, and nothing is coming out of their pocket, you probably won't have much issue.
You'd generally need a permission from other owners for any work in the hallways and such, but as long as the disruption is not too bad, and nothing is coming out of their pocket, you probably won't have much issue.