I don't really take these anonymous sources that seriously. Who knows who they are hearing these things from. Certain people are convinced China will invade by 2025. Looking at China's various endeavors, I don't see any logical reason for them to fast track things.
As for NTC/ETC, it looks like Lianyungang is the northernmost ETC brigade. That is pretty close to Sasebo. However, it is close 2000 km to Misawa. I think ETC can probably be used to attack Okinawa, Sasebo. It can be used to attack as far as air and naval bases around Tokyo if they knock out most of the air defense with ballistic missiles. Shanghai is about 1700 km from Tokyo. Only Anshan and Yanji are notably closer to Tokyo and Misawa. The J-16 brigade in qiqihar can probably be used to attack Misawa. So, I think what they need is a bomber division in NTC.
You don't need NTC to contribute much to Taiwan. You need it to attack Japanese air bases. I would imagine CTC bombers will be utilized a lot too. I don't know how much NTC has trained with other TC to host their H-6Ks.
If it was just one anonymous source, I would have agree. But it's multiple sources and this story has been published and then repeated. And the UK governments must have some sort of analysis as to how they think China will conduct a Taiwan war. Presumably this is reflective of what the US thinks, given the close diplomatic, military and intelligence relationship.
A 2 day operation is plausible from the point of view that China doesn't want to conduct a surprise first strike against the US as the first step, and therefore be in a full-scale war with the US from Day 1.
So I think it is useful to consider what such a 2 day campaign looks like. The UK and US governments certainly won't want to discuss this publicly, so if this happens, we may see ill-considered, populist and plainly stupid decision-making like with Ukraine.
Putin didn't deploy 100,000 troops on Ukraine's border for months just for laughs. Yet Zelensky kept baiting Russia by publicly insisting that Ukraine would join NATO which is a hostile military alliance aimed at Russia. A sensible and competent President Zelensky would have taken the Russian threat seriously, and kept quietly publicly but worked behind the scenes to resolve this. Instead we saw public grandstanding and self-righteousness aimed at the crowd.
Then when the Russian invasion happened, predictions of an imminent Ukrainian collapse were leaked by the Pentagon, and it did take some days for a Western response.
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So broadly speaking, in 2 days, we could say the vast majority of the Taiwanese Air Force and Navy would be destroyed. That the Chinese military can blockade Taiwan and also attack any land target it wishes to. There will no electricity from Day 1 and it will take at least a year to build replacement electricity plants. Much of the dual use civilian infrastructure such as fuel and communications will be degraded at a minimum.
Even if the US military intervenes after Day 2, the Chinese military still retains the ability to keep Taiwan blockaded and therefore ensure the collapse of Taiwanese society within 6 weeks.
So suppose China conducts a 2 day operation with the effects on Taiwan above. Then China declares success and a unilateral ceasefire, subject to Taiwan accepting a Hong Kong settlement but with Taiwan being allowed to maintain its own Army.
This all happens before the US/Japan decide to intervene.
Is it worth the US going to war with China or continuing a war in such a scenario? Would Taiwan confine to resist, knowing it was only a matter of time before Taiwan disintegrates?
Like I mentioned before, we may have the Taiwanese President addressing the UN and telling the world that it isn't in Taiwan's interest to see the US and China at war.
If China and the US are at peace, the world might get away with a short global recession.
But if China and the US are at war, it means a global economic decline comparable to the Great Depression. In terms of the impact to the US and also China, a 25%-35% GDP decline has been mentioned. Japan and Taiwan would be hit even harder.
Japan will also have to grapple with whether it is worth going to war against China. If the US doesn't have access to Japanese bases, there's no way for the US military to effectively reach Taiwan.
But having said all this, I do not think this is China's preferred scenario. There is so much risk, destruction and death in any war. The status quo is fine, particularly since China is still increasing its power in all dimensions.
There are still 400 million poorly paid peasants for example, which can potentially fuel relatively fast growth for another 2 decades. If Beijing is able to make them middle-class and rich, that alone would be the equivalent of an entire USA in terms of people and economic heft.
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Practically speaking, aircraft from ETC airbases could only cover the Western half of Japan, at most.
Yes, I would expect Yanji airbase in NTC to be expanded and new airbases in this area to host heavyweight fighter bomber aircraft.
In the coming decade, I expect more H-6 and H-20 to be assigned for missions against Japan, due to the distance involved.
Of course, that assumes Cuba can use North Korean airspace.