Your Substr() command is starting at offset 10 and retrieving the next 14 characters.

quote:

SUBSTR ("string", start, length)

String
The string from which to extract a substring.

Start

Numeric value representing the offset (from the left) in the string where the substring begins.

Length

Optional numeric value representing the length of the substring. If omitted or if there are fewer than Length characters in the text (including the character at start), all characters from the start position to the end of the string are returned.