Version Naming Convention Lhmcndb Vs Lhmcnda?

[lipvig]

xiaomi.eu_multi_hermes_V7.2.1.0.LHMCNDB_v7-5.0
xiaomi.eu_multi_hermes_V7.2.3.0.LHMCNDA_v7-5.0

What is difference between those two? I don't understand LHMCNDB/LHMCNDA part.
Can you please link me an explaination what all of those characters mean?

 

[lipvig]

L - Android Version
HM - Device code
CN - Region code

Android Version
K - KitKat
J - Jellybean
L - Lolipop

Device code
XD - Mi3/4
XF - MiPad
XE - Mi Note
XI - Mi4i
HJ - Redmi 2
HD - Redmi Note
HM - Redmi Note 2
HC - Redmi 1S
HB - Redmi 1

Region Code
CN - China
MI - Global

I'm still not sure about last two letters. I believe it has to be a version number, but what is the pattern?