As with most legalities in The Middle Kingdom, this requirement must vary by province. I live in Henan (pray for me 
), left and returned to China three times in my first year here and never re-registered with the PSB.... no problems.
That's kinda like saying "It's legal if no one catches you". Did you have any run-ins with the PSB during that interim? If not, I wouldn't bet the farm that your province does not require re-registering.
No run-ins with the local PSB - one of the cops is my 'drinking buddy' and knows I've left China three times (and haven't re-registered).
This thread was the first I've heard of the requirement. My FAO is pretty 'on the ball' and this has never been mentioned. Perhaps they are re-registering me without my knowledge? Perhaps I'm 'illegal' and don't know it? I'm going to ask about it before I find myself fined or detained and deported -
Judge: "Ignorance is not an excuse."
CM:
