missing digits on a 340 engine block VIN?

[95teetee]

I asked my brother to get the VIN off my old 340 block and he gave me the number of '2B30544'.
I thought it should be a 6 digit number after the 'B', but he said his Demon's 340 had a 5 digit # also -the first '3' from the VIN was left off, and just the last 5 digits included (he has a picture of it). Everything in the 'lost & found' thread seems to have 6 digits.
Anyone know if this was a common thing? Or relating to a particular line (like common to Demons or something)?

 

[Rocky_JS]

sometimes it is just a weak stamping. 1972 model year, B hammy car.

 

[95teetee]

I know that it is sometimes, but the picture of my brother's block in his Demon clearly shows '2bxxxxx', with the missing digit being the first mumber of the 'Xxxxxx' usually found there. The five numbers stamped there match the last five of the VIN...