Not sure this make sense.
You want code to say go to next timeline. The timelines are not listed like scenes.
Like in the real world they are a conceptional constructs of what we describe as now and then.
The then can be before or after and direction is only from the stand point of now.
the now being a keyframe and the then being a timeline.
Confused yet.. seemed to make sense to me as I wrote that. 
( maybe @MaxZieb can get the I.A to explain them better.( Being serious ))
Any way you can't do this in the way you are thinking.
What you can do and since you are using code anyway is those the e Start Time line Name...
Was Typing the above when @MaxZieb split the topic.