All speculation without any actual action. When the Nukes are mated with their ICBMs 24/7, we will have clear proof that China is on a Launch on warning posture. Pentagon does an annual report on China's nuclear force. We will see them reporting about it.
Here's what the Pentagon says:
Launch on Warning. The PLA is working to implement a launch on warning (LOW) posture this decade, called “early warning counterstrike” (预警反击), where warning of a missile strike leads to a counterstrike before an enemy first strike can detonate. PLA writings suggest multiple manned C2 organs are involved in this process, warned by space- and ground-based sensors. This posture is broadly similar to the U.S. and Russian LOW posture. The PRC probably seeks to keep at least a portion of its force, especially its new silo-based units, on a LOW posture. Since 2017, the PLARF has conducted exercises involving early warning of a nuclear strike and LOW responses.
Gee, doesn't that sound familiar? Where have I heard that before? Let me call my CMC friend again.