Panzer Corps 2's 'General' and 'Field Martial' editions removed from sale

Before release, there were two special pre-order variants of Panzer Corps 2 available for sale. One was the General Edition, which came with exclusive bonus content, and the second was the Field Marshal Edition, which as far as we can recall was the same as General except you also got the first two DLCs for free.
Those two editions have now been removed from sale. The Field Marshal version makes the most sense as both DLCs covered by that particular version - Axis Operations: Spanish Civil War & Axis Operations: 1939 - have both been released.
In their place though, Slitheirne are offering an 'upgrade pack' that will allow you purchase the General Edition content separately, if you want to.
Unsurprisingly it's called the General Edition Upgrade, and is available for £12.99 as a DLC with the following content:
New Bonus scenarios: 4 brand new scenarios in which you can test your mettle against the AI. Face new, original situations and adapt your tactics to overcome your opponents.
New Camo skins: New 75 exclusive skins are available for your vehicles. In Panzer Corps 2 you can customize the appearance of your units, and with the General Edition you have access to special skins which aren't accessible in the base game.
Digital printable Campaign tree chart: A beautiful hi-res printable artwork depicting the branching single player Wehrmacht campaign in Panzer Corps 2 and which choices you can take.
Digital Wallpapers: 4 hi-res desktop sized digital wallpapers depicting new Panzer Corps inspired artwork.
Digital Soundtrack: 16 beautiful tracks composed by the talented Bill Meyers, Dan Bewick and Alexander Shargin, inspired by classic movies on World War II. Available for download as high quality .mp3 files.
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