\ban ASCII word boundary
DELIVER TO:the literal text DELIVER TO: (case sensitive) \Ra newline sequence
\s*any whitespace character, repeated any number of times
\S+any non-whitespace character, repeated at least once
.*any character (except for line terminators), repeated any number of times
Non-Capturing Group(?:\R.*){2} {2}repeats the group contents below exactly 2 times:
\Ra newline sequence
.*any character (except for line terminators), repeated any number of times
.*any character (except for line terminators), repeated any number of times
\hany horizontal whitespace character
\S+any non-whitespace character, repeated at least once