Took DEP boat out of Barnegat this morning to hot swap optode. SN #1504 removed, SN #971 installed (along with bracket). Appears to be working correctly now, so will need to troubleshoot optode w/ new cable in lab. Also need to see if it can be repaired/replaced under warranty. Glider currently headed to 6th waypoint in standard path, 1 hr missions. Changing to 2 on next surfacing.