US citizenship from China?

I will be eligible to file N400 for US citizenship in October but I am looking at a job that will transfer me to work in China within the next few months.

I will come back to file N400, do finger print, interview, etc. but am just not sure if this transfer would cause any problem with my citizenship application?

Do I necessarily need to file N-470 to preserve residence since I am so close to file N400? N-470 requires the employer to provide a complicated affidavit; I am not sure if my company is willing to do that.

Anyone with similar experience please share. Thanks in advance!