Much appreciated MrBadE, thanks, I think I've got the hang of it now.
Here's another, worthy of a film, a short one though I'll give you that. Alec Guinness, Stanley Holloway, Sid James and little Alfie Bass.
Often you will find diferences to Copper pennies of most years were letters / colons were re cut and repunched to continue using the same dies.
Both your coins are OT Far colon after DEF, The re punched different position of colons IMO does not really mean any major variety and if it did there would be lots of different types.
The main varieties for 1855 are......
OT Far colon
PT Close colon
OT Three colons after FID
One with a DOT on Victorias Forehead.....A variety for some but only a flaw
You really could go on forever Paddy ,so you can make your own judgement as to what is a variety or not 😉