there are a few periods of different fundemental strategy
1

eople's war,
this is in Mao's era, it is basically fighting a war against a better-armed enemy, luring the enemy into deep where a lot of ppl and attack the rear of enemy or supply line of enemy with superior number in some points...(human wave?)
2:People's war under modern conditon
probably started by Lin Biao, once the minister of defence, probably because they saw the tech in U.s and soveits armies are so good and numbers are useless anymore, they start to think they should fight with people's war but with better tech, this period is around 1970s
3.Limited war
this theory rose after the first sino-vietnam war, when PLA didn't perform as expected, also during that time Soviets are declining and relationship with U.S is getting better,
therefore, a total war with either Soviet or U.S is not possible, but more and more small wars like Sino-vietnam, or Sino-india, or CHina-taiwan are possible, so this theory led a large scale of cutting useless personels and ready to fight a small war or regional war rather than a total war
4.Limited war under modern condition
started in 1990s after seeing how U.s army used high tech to beat up Iraqis. PLA starts to reduce more troops and upgrade C4ISR, invent new tech, equip new weapons and also train troops for fighting a high tech war
this strategy i think is primairly aiming at Taiwan, PLA is ready to invade taiwan in a style like U.S invades Iraq, that is why PLA arms 600 missiles at taiwan and equiping 3rd generation jet fighters.
today PLA is still a relatively large army and capable of fighting a total war and defeating any invading enemies in a total war BUT not under high tech, PLA is not there yet, maybe 10-20 more years