In addition to getting payments going back to your application date, you can get up to 12 months of retroactive payments for the year prior to your application date (or your protective filing date, discussed below) -- if you were disabled that long ago.
Characters will receive one specialization point at level 7 and another at level 14. Specialization points can be saved for later levels or used mid-level (the Level Up button on the stats sheet will be active if there are unspent specialization points).
In order to level up Mastery Rank, you need to level up gear (frames,weapons,sentinels and their weapons, and now Kubrows). And when the XP is enough your Profile will have an orange pulse, you click on it and take the test.