Sadly, got AA memo about McLean's end just now (1,6,3)

'now' is the definition.
I know nothing about this answer so I can't judge whether this works.

'sadly got aa memo about mclean's end' is the wordplay.
'sadly' indicates anagramming the letters.
'about' means one lot of letters goes inside another.
'end' indicates one should take the final letters.
The final letter of 'mclean' is 'n'.
'got'+'aa'+'memo'='gotaamemo'
'gotaamemo' is an anagram of 'amometago'.
'amometago' enclosing 'n' is 'A MOMENT AGO'.

'just' is the link.

Can you help me to learn more?