You don't get anything back because there is nothing to get back. You get hero points when you level. Throughout levelling to 80, you get exactly enough hero points to unlock all base specializations and skills. Any hero points you get in the world just allow you to get those unlocks sooner, and once you are level 80, can be used to start

The points the boost uses to unlock all specializations and skills are those from leveling up. The boost is just a level up to 80 along with some basic level 80 gear so you can actually play at level 80. Why would it give you extra skill points? Also, using your boost on a level 71 character seems like quite the waste of level 80 boost.
Long answer: you basically get Hero Points as you play/level up, you then put those on any of the specialization trees but by the time you hit lv80 you should have points in everything. The 1 to 80 experience is more of an unofficial extended tutorial experience rather than the game itself so you dont have to worry if you put points in the
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Some are easier than others. (may require other masteries) XP: get xp in the right region to fill up the selected mastery bar. When it is full you can spend the mastery points to unlock the mastery. Good ways to get XP are doing events in HoT maps and doing fractals. For XP, u have two differend kinds of expierence. At level 80 you will have enough to get them all. If you do hero point challenges in the world, you will be able to unlock skills and traits even faster! If you want to let your pet to take aggro while you shoot them from afar, beastmaster -> marksmanship is a good way to go. A Zerg and Solo Hero Point Guide for Heart of Thorns! Many different ways of getting to each Hero Point, Masteries along the way, and best practices for comm
8 skill points are earned at levels 20, 26 and 32. 7 skill points are earned at levels 38, 44, 50 and 56. 6 skill points are earned at levels 62, 68, 74 and 80. Only when you are level 80 you get a skillpoint when your experiencebar fills up now.
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