See the last post of your own thread:
Is this for a very small system with extensions in the range of 100-119? If so, then try this on the S505:
{911|1[2-9]xx[2-9]xxxxxx|[2-9]xx[2-9]xxxxxx|1[01]x}
with Dial Timeout Now set to 1. (This is simplified and doesn’t include feature codes, etc., for which you will likely use open-ended patterns)
If you have extension numbers such as 121, then a timeout is required to distinguish from e.g. 12125551212. I suspect that the S500 series is not smart about timeouts.