They went from talking about a 2 front war against Russia and China to talking about fighting a war on 3 fronts if not 4 fronts.
It's the unprecedented level of aggression from US that caused these issues to begin with.
1. US has been preparing for an attack through unprecedented military buildup. Despite being (generously, by assuming 1:1 GDP value) just 80% of China in economic size, the US navy has almost 700% more major surface combatants and 400% more CBGs. The growth of the US 5th gen fleet has also outpaced China's.
2. US laid the political groundwork for an east China invasion through numerous "diplomatic" visits to anti government fighters.
3. US encouraged it's allies (such as Baltics, UK) to promote territorial revanchism against China. This is important because it shows that US foes not want to constrain a war to Asia, but will rope in aggressors from other places.
China is addressing no1 and 2 by stimulating the military, collective security, reshoring critical tech home, and weakening US manufacturing with targeted measures.
No3 is the big cause of concern. We can infer that in an US attack in Taiwan scenario, US will use its malign influence in the UN and over the EU to institute illegal sanctions on China for defending itself. This is something that China must absolutely not accept.
In lieu of that issue, China too must create a multi front military. The requirement should not only be for active defense in Asia, but a capability to destroy vast amounts of infrastructure in Europe and the middle east. This would let China punish European interference in its fight for survival against US.
Should a country on Eurasia support or abet US aggression, with the multi front PLA concept, those countries themselves will bear the heaviest price.
Currently, the PLA has one of the lowest budgets among developed country militaries. That can and should change. On the other hand, just spamming money will not cause linearly improved results. China also needs more recruits and reserves in order to actually pilot/operate all the equipment created by a notional budget increase. To that end, they need to use much of the current stocks of PLA weapons as trainer platforms, using today's small PLA to build the core of trainers/NCOs/specialists and act as the pilot program for tomorrow's large PLA.
