Touching notes and informal apology about the author's withdrawing something from Brewer's? (11)

'touching notes and informal apology' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'the author's withdrawing something from brewer's?' is the wordplay.
I cannot quite understand how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is located in the answer.
'author's' could be 'im' ('I am' referring to the author of the crossword) and 'im' is located in the answer.
'something' could be 'er' (I've seen this in other clues) and 'er' is present in the answer.
'from' could be 'o' (I've seen this in other clues) and 'o' is found in the answer.
This may be the basis of the clue (or it may be nonsense).

'about' acts as a link.

Can you help me to learn more?