Expired Annexure 18 and a 5 year resident card

Hello,
I have a 5 year resident card valid until Mid 2017 and don't require a work permit. I had moved out of Belgium temporarily with a Annexure-18 that expired in end of March 2016 as I couldn't travel due to the travel advisory provided. I have now been offered a job and so my question is can I now travel to Belgium with my still valid resident card and also do I need to get a fresh Work Permit since my Annexure-18 is no longer valid?
Please advise.
Thanks and Regards,
FoodieJunkie