PoD states that "According to the charts of the Imperial Scouts, the planet still has a Class-A Starport, but the charts are centuries out of date. Drinax is a dead world. There are no settlements on its surface, only the scars left by the Aslan when they bombed the cities from orbit. The once-fertile grasslands were seared to deserts; the forests where the kings of old hunted were razed. The seas bloom red with algae after they were boiled to death. No-one lives on Drinax anymore." If we take this literally, then that means that the UWP for Drinax is taken at some point before 885. Traveller map lists the population at 70,000. This being pre-apocalypse number is further affirmed by the line in PoD2 stating "The survivors of the invasion, numbering a scant few thousand, had to adapt to survive."
So, knowing the UWP is out of date for population, there's lots of room in there for a referee to assume its out of date on other factors. If we take the "boil the seas" bit literally it quite probably would have lost a hydro point or two and we could take the extreme weather to indicate some kind of major shift in atmospheric density: "Ever since the Ahroay’if bombed Drinax from orbit, the planet’s weather has been temperamental. Huge dust-storms in the upper atmosphere cause sudden temperature drops, resulting in fierce flash storms below. Regions once covered in thick forests are now empty desert, with nothing to catch rain or slow winds."
I feel like if you want to have the Vexspies to be hiding old Drinaxian treasure caches, a good source of conflict there is with Oleb. As we can see from Shadows of Sindal, he's the sort to really invest resources in hunting down rumors of caches and buried treasures. If you want a story seed related to it, perhaps he dispatches the Travellers to go investigate a valuable cache he has documented from pre-fall days, in an area that has hitherto been inaccessible due to weather or plague, only to have the Vexspies also be trying to lay claim to it, forcing the Travellers to pick a side.
In PoD2, on the Wasteland Life Event table, one of the possible results is...
"When you were a child, the tribe’s wise-woman cast broken stones over your crib and declared that you were the Hlax Kur Eaisa, the messiah who would avenge the Vespexers upon the Aslan who ruined their world."
Per PoD2, "Below the Floating Palace, Drinax is a wasteland. The Aslan dropped rocks from space on much of the planet. Dust clouds choked the skies for years, plunging the whole planet into a long impact winter. Major population centres were blasted with plasma weapons and disease bombs; millions died at the claws of the conquerers. Two hundred years later, the planet is slowly healing. Green shoots cover the impact scars, and new forests are growing in the ashes of the old. It will be another thousand years before the planet is close to its former vitality, and some wounds will never heal. The spores of the Aslan biological weapons still sleep in the overgrown ruins of the cities, so Drinax may never be safe foR human occupation."
So yes, it is regrowing, but I had always read that as just meaning it's an ancient, weed-grown post apocalyptical hellscape rather than a fresh one. I feel we see more of it still being a horribly inhospitable place than we do it being a world recovering, but your mileage may vary.
I am changing the UWP a bit -- my Drinax is A*64445AF* {1} (B343)
The asterisk on the Starport is covering the fact that the UWP is actually reporting (the Royal Staryards on the Floating Palace) the looted remains of a class A starport -- what is truly there & operational is between a D and a C. With effort, expense, and adventures, the players can rebuild to class A much faster than the normal sixty year timeline from T4 'Pocket Empires'.
The asterisk on the TL reflects the Scholar's Tower -- much TL15+ knowledge is preserved, but there is no infrastructure, tooling, materials, or trained labor pool. Some items can be laboriously hand-crafted over long timelines, but they are expensive and prone to quirky behavior from being one-offs. Even so, most of what has been built by the Scholars Tower in the last twenty years or so is TL14 (or less) stuff. Drinax is more like TL9 in the Floating palace, and TL4 or TL5 among most of the Vexpexer tribes. Uplifting the overall TL of Drinax back to 15 would take 209 years by T4 'Pocket Empires' rules -- but excessive spending can reduce that to 105 years, and I will allow for surviving caches and folks from shelters to (along with excessive spending for 'Accelerated Construction') do it in 53.
The population of the Floating Palace is ~70000 people; and is what is reported on the UWP. The Vexpexers are more numerous, and (when they are not ignored) vastly under-counted.
The 'resources' reflect the non-spacefaring nature of campaign-start Drinax -- none of the off-world resources are being tapped; and any old infrastructure to make use of them was thoroughly destroyed. 'Labor' can be drastically increased by thawing & recruiting folks from the shelters; but the world has to be able to support them first, so thawing them all out all at once is unwise. 'Infrastructure' would normally take 16 years per point of improvement; 176 years to return Drinax to the original value. I think I will make improvements up to 9 faster (some of the 'destroyed' infrastructure can be salvaged, repaired, & re-used), so from 4 to 9 will be 40 years instead of 80; full restoration would then only take 156 years (less, with excessive spending).
I am figuring the pre-bombardment UWP was more like A666A5AF {5} (G9F4); without any assistance or special effort, it will recover to basic habitability at around 1385 (the 500 year mark); it might grow up to a lush world in another couple hundred years after that -- but spores, toxins, and radioactives will lurk in a layer of soil not far below the surface. Plowing a field might release (a few spores of) a weaponized plague. There are no rules in T5 'Pocket Empires' for terraforming; but I figure Drinax might be able to get from Atmosphere 4 (thin, tainted) to Atmosphere 5 (thin) with 30 years of active work, and to Atmosphere 6 in another 60 -- neither will change naturally.
Unless a player rolls it, I am not likely to have a
Kwisatz Haderach Hlax Kur Eaisa in my game. The Fifth Frontier War and the assassination of Strephon are likely to be enough of a challenge without piling on an all-out genocidal war with the Aslan. As it stands, the relations between Drinax and the Ahroay’if are already in a state of flux -- with Kasiyl maybe being an outcast or not, the player group maybe saving the life of the Ahroay’ifko or not, the relationship between the Tlaioawaha and the Ahroay'if maybe being strained or healed by the players, etc.
I think I may change another aspect of history -- maybe it was the Tlaioawaha who mustered the fleet & bombed Drinax. It makes the Tlaioawaha more of the mustachio-twirling villians of the PoD campaign, and clears the way for the Ahroay'if perhaps being recruitable. It also seems like Aslan politics is more tumultuous than a steady 220+ year status quo of "The Ahroay'if (a rich minor clan) are vassals to the Tlaioawaha (a major clan somewhat in decline)" -- this way, we can see the Tlaioawaha decay from a bunch of blood-and-thunder warriors to their somewhat decadent modern state & the corresponding rise in the fortunes of the Ahroay'if over the same span.
In addition to the UWP changes, my Drinax is the satellite (a far moon) of a small Gas Giant which is in the Habitable Zone of the star. This allows Drinax to not be tidally locked, and have regular days and nights, and (if desired) seasons -- plus a spectacular veiw! Of course, I need to figure out the effect of Jump Masking from the gas giant... trips to and from Drinax might take longer than normal for a world this size.