Starting characters (Battle Rank 1) begin with seven (7) Certification points. As each Battle Rank is earned (with the exception of Battle Rank 6, 12, 18, 24, 25, 28, 30, 32, 34, 36 and 38), so is a new Certification point, up to a maximum of 34 at Battle Rank 39. At Battle Rank 40, all certifications will automatically become available to a player, removing the use certification points.
If you choose to "forget" one of your certifications, the certification points spent on it become immediately available to be spend on other certifications. If you "forget" a certification that is a prerequisite for another certification you have, both will be forgotten automatically.
Example: If you "forget" Armored Assault I; Armored Assault II, Flail, BattleFrame Robotics, BFR Anti-Infantry and BFR Anti-Aircraft will also be forgotten if you have them certed. Note, however, that you will not be able to "forget" another certification for 6 hours.
Characters newer than 7 days, can unlearn certifications without penalty. After those 7 days however, the 6 hour timer will apply. Occasionally, your character may be granted a "Forget All" option, normally coinciding with the release of a major patch, enabling a one-time reset of all certification points.