Legal Rights?

I worked for a company for 3 months, they had to retrench me due to finances, and they are now offering the same job, a few months later. I left on good terms and was assured (in writing by the boss) that this was due to financial reasons only. My question is some people are saying this position should be offered to me 1st due to my retrenchment, this they believe is correct by law. I have approached the company regarding me working there again, and have not had any response. Any help/advice regarding my situation would be greatly appreciated. Thanks in advance