You put things nicely in perspective for me. At some stage of the application I have been told I will be sent to the big city (small by chinese standards) where secretly we want to live and to move to. Do you see any important complications about that at all, if after receiving our passports back with residence permits we suddenly announce to the local police that we are off to live in the city?

I suggest to you that you stop thinking in terms of 'we'. You are an alien in the eyes of Chinese immigration, but not your wife. She decides to move to the city, not you nor 'we'. It's much easier for her to do so than for you. You tag along as you are her alien appendage. Your reason for changing your digs is merely to be with her. Her reason for changing her digs is her business.

So, get your RP organized while living in your sparrow-fart village/county. Then report to the PSB THAT YOUR CIRCUMSTANCES HAVE CHANGED, IN THAT YOU HAVE HAD TO MOVE TO THE BIG CITY TO BE TOGETHER WITH WIFEY.

Your RP WILL BE IN EFFECT UNTIL IT EXPIRES. THEN RE-APPLY, THIS TIME TO THE BIG CITY PSB.

Ensure that your wife isn't caught out lying, coz that would possibly have negative consequences. You and your wife should be able to sing from the same hymn sheet, to the letter, if necessary.