A research found that there are many career paths seafarers can take when they move ashore in Britian, such as pilots, agencies, lecturers in maritime schools, harbour masters, maritime lawers, surveyors, officers in Maritime and Coastguard Agency and Maritime Accident Investigation Branch, positions in P&I Clubs and other maritime insurence companies, and of course positions in ship management and shipping companies, etc. With the seafarer pool dwindling each year, the developed countries are worrying about where to find ex-seafarers to fill up these positions.This research also found that in Poland there are no such career development paths. I think this is also the case in China.

If somebody interested in the comparison between Chinese seafarers and Filippinos, you can read CHINESE AND FILIPINO SEAFARERS: A RACE TO THE TOP OR THE BOTTOM? (page 73) from http://www.sirc.cf.ac.uk/Symposium%20Proceedings%202003.pdf
If you don't have the patience to read the whole paper, you can only read the conclusion on page 95