The new DLC is supposed to come today but nothing is certain before it is here. I think the v 8.0 of the base game is in good enough shape to be released but we will see.

CORRECTION: The free update brings diplomacy itself. The DLC brings some underhanded "diplomacy" capabilities, terribly sorry for getting it wrong.

Name of DLC: X4: Envoy Pack

It's available now.

One can buy it (I already did) - but it is not available yet for download [for me]. Neither through GOG Galaxy nor in the offline file sections (neither for windows nor linux).

@OP

The topic headline is misleading IMHO - there is a new update 8.0 which is "the diplomacy update" and there is an envoy DLC. While the espionage theme of the ship DLC can be considered "diplomacy" it is misleading here - the main diplomacy features are added via the free patch, not the new paid content.

The Linux version was not updated yet (it's still 7.6) but I can see the offline installer for the Envoy Pack in the Windows version. I didn't boot Galaxy yet, and I won't be able to do so for a while, so I can't say f it's available there already or not, but it should be...?

GOG Galaxy is patching the game right now. It took almost an additional hour to get to that point - restarting Galaxy multiple times as well as the PC doesn't change anything. I'd say the files weren't available yet on the GOG servers - or some countries couldn't get the updates yet.

Hmm - The off-line download page says that the download files are 8.0, but the downloads themselves have the description "8.00plusdlc_rc3". Are this the old Release Candidate 3 files? Or are this the full 8.00 files with wrong description?

Even the new DLC is "numbered" as such...

I am a bit confused about this.

Quite possibly the RC3 was found acceptable and there was no file changes.

The "advertising" text, on the wiki.egosoft homepage, currently says "The most prestigious ship for Diplomacy..." without putting diplomacy in quot marks itself :) .
But yes the main Diplomacy part should come for free with the 8.0 update.
Still waiting for Linux version to be released.

Was the FSR 3 Native AA in previous patch? Image quality is amazing in that mode and performance hit is comparable to TAA.

Aye, it's really sad how GOG treats linux users here. Egosoft has provided everything to GOG and it's GOGs same old same old slow manual process of bringing the linux files live -.-

Here's the official dev response: https://forum.egosoft.com/viewtopic.php?p=5290325#p5290325

"I must admit, I am beginning to feel a bit tense."
Boso Ta

... and me ofc :-)

Pretty poor eh. I just refunded the Envoy Pack; GOG shouldn't be offering it for sale if it's not ready, or at least clearly mark it as a pre-order for Linux customers.

I'm looking forward to it, possibly starting a new playthrough (skipping timelines to Quettanaut). I find it cool being able to run around in ships. Though I'm full of bruises from the Hyperion's slightly non-ergonomic interior lol.

Agreed - selling a game on release date has to make sure the version is ready on their infrastructure. Not even mentioning it that their manual processes postpone the availability by days is a no-go.

They really should stop pestering people with GOG Galaxy surveys and instead work on their deficits in their linux distribution pipeline! :<