Hi,
CleverPhD has a great response, but I wanted to add specifically that if you do this move, you will not lose the authority of those 13k links / 1,200 linking domains if you do the 301 redirection process properly. The guides linked to in CleverPhD's comment will help.
301 redirects pass the majority of authority from one URL to another, but you may also want to create a list of the top linking websites from that 1,200 and contact them after you have completed the move, asking them to update their links to you. This will ensure that you retain your best links on top of properly redirecting all the others.