miyoko
Yes, you should take another job if something comes up. You can always resign during probation any time without any explanation. That's how it goes all over the world.
You haven't heard anything for a very long time. Was there an agency involved? If yes, you should contact the agency. What happened to one candidate was that her file was not even forwarded to Dubai for many weeks! The agency in London forgot to send her an e-mail that she should make new photos. The candidate wrote and left a message for Emirates after 6 weeks of waiting. They got back to her 9 weeks after the FI and told her that she needed new pictures. She received the Golden Call 3 weeks after sending the pictures.
Your file must have been misplaced. This is waaaay too much time without any news.