Zipline not moving forward properly

[curiosikey]

Watch purple zipline not being moved forward despite creeps being well ahead of the location it's stuck at.

Twitch clip: https://www.twitch.tv/lefaawr/clip/SuccessfulPeacefulPeanutCurseLit-zpHrk53tJWkymvCy

Game ID 19340494

Time of occurrence:

• 31:22 ish is when the zipline should start moving forward with the creep wave.
• 31:35 creeps from both teams interact in purple lane at roughly Sapphire's tier 1 location, but zipline is back at Sapphire walker location