Is there a way to switch to Reply All after pressing Reply in Outlook 2013?
Solution 1:
No, it is not a "one button click" way to do this.
You have two options:
Copy the recipients of the original mail and paste them into the "Cc" field of the new mail you are composing.
As you said yourself, copy the text you have written, and start over by using "Reply all".
The first option would probably be easiest.