How to get .vtt files with multiple PTS entries

[flvlef]

Hi @eggoynes
In this reply you mention the way that MediaPackage is handling the .vtt files it gets.
Using the same mechanism, do you have any idea of how to have multiple entries?
e.g. (MP would output):

WEBVTT

01:00:05.000 --> 01:00:05.500
What was

01:00:05.500 --> 01:00:06.000
What was his

01:00:06.000 --> 01:00:06.500
What was his name 

01:00:06.500 --> 01:00:07.000
What was his name again?

What would be the Lambda@edge output to make sure it would be handled well by MediaPackage?
Thank you.

cc. @diogofirmino