Hi Hou
What version of Stat Server are you using for WFM? If it's an older version, you should check the release notes as I know a few defects were addressed going back about 2 years that would have been causing some WFM statistics to not be what you expect. I vaguely remember at least of them had to do with things like ACW etc.
It would also pay to check what metric you're using for the AHT against your WFM activities and whether any filters are included. Without knowing and seeing your configuration there could be a number of things causing unusual discrepancies, from short abandons to what you've already mentioned around the handled vs arrived interval.
I wouldn't ever look for any "relationship" between GCXI and WFM. The predecessor for GCXI was GI2 and there have been a number or blogs and articles written over the years over why you shouldn't be trying too hard to "match" the reporting layer to the WFM layer. If you believe it's a huge discrepancy then you may need to talk to your Genesys partner or raise a case to Genesys Care after checking Stat Server versions and statistic definitions as I've said.
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Vaun McCarthy
NTT New Zealand Limited
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