Help with wit yoot spk please breadbins

[Spare tyre]

Our local friendly motorbike thieves are posting their antics on Instagram, pretty depressing and frustrating for sure


Looking at a lot of their user names they are of this format

yj.13.2
yr1_14
mk14_s
yjs.4s

Etc etc

I’m not suggesting for a sec these are the wrongungs, mostly the commenters on the iffy motorbike pics

What does the format mean, they all seem to have a variation. Is it age postcode ?

Cheers

[anonymous-user]

Its nothing relevant, just hiding their real identity so they can be all internet hard without fear of reprisals and ting.