Bert Identification Number

Bert Identification Number is one of the systems required to be used by fictional characters before they can be dressed as a character from The Littl' Bits.

Composition
The format is iiiiyycmdxxxxaaasz, where: Note: The number 0 is often slashed or dotted to prevent confusion with the letter O.
 * iiii denote initials
 * yy denotes year of birth
 * c denotes century of birth (from A = 16th century to G = 22nd century)
 * m denotes month (from A = January to L = December).
 * d denotes day (1-9 for day 1-9, 0 for day 10, letters ABCDEFHIJKLNOPQRTUVXY for days 11-31)
 * xxxx is the computerised four-digit number
 * aaa denote the character's age in base-20 number (for age unknown, aaa is replaced with 0XX)
 * s denotes sex (M = Male, F = Female, U = Unknown)
 * z denotes a check character (values: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, J, K, L, M, N, O, P, Q, R, S, T)

Month
To indicate month, letters are used in alphabetical order:
 * A = January
 * B = February
 * C = March
 * D = April
 * E = May
 * F = June
 * G = July
 * H = August
 * I = September
 * J = October
 * K = November
 * L = December

Date
To indicate date, 1 to 9 indicates the 1st to 9th day of any month. To represent other days: 0 represents the 10th day of any month, while all the letters of the English alphabet except G, M, S, W and Z to represent 11th to 31st day of any month.