broke in .40. I can't send events to elastic using a datastream index

[data-dude]

It seems the elastic output doesn't work with datastreams. Elastic datastreams expect a timestamp with a header and when I try to send to a datastream it fails saying it expects a timestamp field in the header.

This was working with 0.39 but broke with 0.40

would anyone know how to set timestamp in elasticsearch.customheaders ?

[data-dude]

i setup a regular index using lifecycle management as a work around but it'd be nice to use elastic datastreams