I'm not sure if this helps as it was based on the UK versions, but it does explain other countries below. It's an old document that I found.
Nortel Product Codes for Meridian 1 UK Products
ARIES TELSETS:
i.e. M2006, M2008(D), M2216, M2616(D)
M2006 - NT2K05Cx-and the appropriate colour suffix or NT2K05Ex -and the appropriate colour suffix
M2008(D) - NT2K08Cx - and the appropriate colour suffix or NT2K08Ex - and the appropriate colour suffix
M2216 - NT2K18Cx - and the appropriate colour suffix
M2616(D) - NT2K16Cx - and the appropriate colour suffix or NT2K16Ex - and the appropriate colour suffix
Colour suffix: -03 Black, -93 Dolphin grey, -35 Ash/Beige/Chameleon.
!!! Key tip - the C or E denotes UK product and any other letter means that the telsets is not UK product. !!!
ORION TELSETS:
I.e. M3110 / M3310 / M3820
M3110 - NTDL01Bx- and the appropriate colour suffix
M3310 - NTDL02Bx-and the appropriate colour suffix
M3820 - NTDL03Bx-and the appropriate colour suffix
Colour suffix: -70 Charcoal, -93 Dolphin grey, -35 Chameleon.
An example of an incorrect code: "NTDL22AB-35
The 22 is not appropriate and should be 01, 02 or 03 for UK product.
The AB is not appropriate and should be BB, BC, BE, etc (the first letter of the 2-letter code should begin with B)
!!! Key tip - the B denotes UK product and any other letter means that the telsets is not UK product. !!!
All the best
Firebird Scrambler
Meridian 1 / Succession and BCM / Norstar Programmer in the UK
If it's working, then leave it alone!.