Ports 27 and 28 are combo ports.  See 11863.6.10.58 as an example.

Also, the doSwitchSNMPmining function should be updated to support this model (so the AC & console ports get added).
Add "case preg_match ('/^11863\.1\.1\.1/', $sysObjectID)" above the "case preg_match ('/^11863\.6\.10\.58/', $sysObjectID)" line and move the "// TPLink" comment accordingly.