Ashes of Phoenix - Build Slots

When do I unlock more Build Slots? (Currently every 15 Account Levels)


Build #1 Level: (First Build on Register)
Build #2 Level: (unlocks at: 105,000 XP)
Build #3 Level: (unlocks at: 435,000 XP)
Build #4 Level: (unlocks at: 990,000 XP)
Build #5 Level: (unlocks at: 1,770,000 XP)
Build #6 Level: (unlocks at: 2,775,000 XP)
Build #7 Level: (unlocks at: 4,005,000 XP)
Build #8 Level: (unlocks at: 5,460,000 XP)
Build #9 Level: (unlocks at: 7,140,000 XP)
Build #10 Level: (unlocks at: 9,045,000 XP)

Total Virtual Level:
Total Virtual XP:
Next Build Slot in: XP