No information regarding planned content or release date but there is another Development Update being worked on. See https://www.nomanssky.com/2019/11/beyond-development-update-4/

I know it's a small thing but I really wish that HG would fix the various dialogs. "Old hands" recognize that the Captain of the freighter you just rescued doesn't really make any sense. Aliens at trading posts have bits of old conversations that aren't meaningful any more given that they're only walking dictionaries, now. Even the teleporter prompts are subtly wrong.

Grumble, grumble ...

And the references to old mats/items like heridium, plutonium, etc. I wish they'd clean those up as well.

That aside, I'm actually pretty pumped about a focus on bug fixes and QoL improvements.

Looks like the expected release date for Development Update 4 is next week as I saw that someone had found this:
https://www.facebook.com/NoMansSky (currently the first post and contains the phrase "something cooking in the kitchen for next week."

Quoted from the Development Update 4 webpage:

" We’re currently in the process of grouping these into something we’re calling the Synthesis update, and we’re excited to be able to let you know that this update is planned for release very soon. Whilst in the background we continue to work on new features and content, in the meantime Synthesis is about bringing together polish and small quality of life improvements to address many of the requests we see from the community. We look forward to sharing it with you! "

The statements by Sean on the update page & facebook = " This update is planned for release very soon. " and "something cooking in the kitchen for next week."

Does that mean we are going from BEYOND update to SYNTHESIS update in the very near future ? Maybe next week or so ?

Development Updates to date have only been for Beyond so it seems more likely that Development 4 is for Beyond and Synthesis would be sometime in the future.

Looks like they might have changed things or perhaps combined Development Update 4 with Synthesis as Development Update 4 was not released in Experimental but earlier today Synthesis was released (and possibly a day earlier than posted).