yes - it will get new work probably within about an hour of the connection coming back up (like SS said the retries get longer and longer apart so if it had been trying for 6 hours it may still take a little while after the connection is sorted) and will try to send the finished WU every 6hrs as standardmikeymike said:.... after 6hrs would it still upload happily?
you can force it to send/receive by restarting the service/client as it send and receives and work at start up anyway