Woke up today and tried multi-dialing as a routine, only to surprisingly find that 2 dials are now possible:

Has Chengdu Telecom found its conscience? Could it be a May Day holiday special promotion??
No rush to reallocate incoming and outgoing traffic to Line 2 yet. Let's observe for a few more days to see if it stabilizes and if it will restore to 3 dials... Really looking forward to it.