We had some EDI files that were clogging our system, I found some data that was outdated and most likely confused the shipping system. I also found some spaces where there shouldn't be any:
. . . |LB~TD5||2| FEDEX|T| FEDEX~REF|2I| . . .
Note the spaces at the beginning of the FEDEX segments. I am having trouble finding good documentation for X12 856 EDIs. Would this white-space matter? I have removed it since it is not required, but should I bother looking out for this as an issue in the future?
The whitespace shouldn't matter (as long as it doesn't appear in the ISA segment), as most translators will base their process on delimiters. Most translators worth their salt will also support some kind of Trim() mechanism that you can strip the whitespace. It is certainly bad practice, and you can ask your trading partner to knock it off, but if they can't, you should be able to strip it during translation.
The whitespace could be an issue if you're cross-referencing the FEDEX value (TD503 and TD505, it looks like) to a code in the shipping system, but shouldn't "clog" any system.