ZCH is the new designation for the Champaign office in OCLC ILL only not LINC.
When sending ILL requests in LINC, continue to use the LINC codes. If LINC says to send an item to LTN, please continue to check on whether or not it is a non-automated building versus a person at IHLS-Champaign.
If it is a non-automated building then you should check your item out to that building. You can find the instructions for this in LINC Circulation and Holds booklet (page 13 - depending on your version of the booklet).
If you have any questions, contact Donna Schaal at 217-352-0047 ext. 204 or firstname.lastname@example.org.