Day One, Two, Three ... could be start of original new version of this? (3,4,3)
I believe the answer is:
the year dot
'two three could be start of original new version of this?' is the definition.
I don't know anything about this answer so I can't tell whether this works.
'day one' is the wordplay.
I cannot quite understand how this works, but
'day' could be 'd' (abbreviation for day) and 'd' is found within the answer.
'one' could be 'the' (both can introduce a definite example of something) and 'the' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for the year dot that I've seen before include "date, one imagines" , "Time's beginning" , "The beginning of time (colloq.)" , "right at the start" , "A very long time ago" .)