You can decode your Mavic Serial Number using the tool: http://tools.retroroms.info/

Here is the format, you look at the 5th, 6th and 7th item. 

Ex    : 08QDxxx ........
  * 5th -^         = YEAR
  * 6TH --^        = MONTH
  * 7TH ---^       = DAY

YEAR
  * D = 2016
  * E = 2017
  * F = 2018

MONTH
  * 1 = January
  * 2 = February
  * 3 = March
  * 4 = April
  * 5 = May
  * 6 = June
  * 7 = July
  * 8 = August
  * 9 = September
  * A = October
  * B = November
  * C = December

DAY
(base36) (base10)
  * 1 = 1
  * 2 = 2
  * 3 = 3
  * 4 = 4
  * 5 = 5
  * 6 = 6
  * 7 = 7
  * 8 = 8
  * 9 = 9
  * A = 10
  * B = 11
  * C = 12
  * D = 13
  * E = 14
  * F = 15
  * G = 16
  * H = 17
  * I = NOT Used as I and 1 can be confused.
  * J = 18
  * K = 19
  * L = 20
  * M = 21
  * N = 22
  * O = NOT Used as O and 0 can be confused.
  * P = 23
  * Q = 24
  * R = 25
  * S = 26
  * T = 27
  * U = 28
  * V = 29
  * W = 30
  * X = 31

credits to Logger at mavicpilots