The same problem using Web Studio.
Something that can help you:
When you create a new time line, you can see upon the screen line, the ruler with the time division with the length of the created timeline.
Yo can reduce the duration of the timeline and you will see still this ruler.
But, if you try to increase the duration of the timeline, you don´t see any time division after the original length of the timeline.
In the attached picture you can see in green the original timeline length (it was 1 minute), with the corresponding time divisions.
In the red elipse, you can see that the system does not assign the corresponding time divisions for the 40 additional seconds I gave to the timeline.
I think that´s a bug.
I hope the description of the problem can help you to fix the problem.
Exactly the same occurs using Desktop Studio.
Diego
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