I am not able to filter the customer elements with fixed demand patterns in the flex table of customer elements. Other demand patterns can be filtered successfully, but the not the fixed one. When we go to custom filter, the option of FIXED demand pattern is not listed in the custom filter.
However junctions with fixed demand patterns can be successfully filtered in the demand control center.
Currently fixed demand pattern option is not listed in the query builder of custom filter; we have logged a defect for this - #276741.
Though there is a workaround to achieve this.
It appears that other demand patterns have IDs in the query builder of custom filter, whereas there is no ID specified for fixed demand pattern, so it appears to be NULL. So type the query as Demand_DemandPattern IS NULL in the query builder of custom filter and click on OK. It should filter the customer elements having the fixed demand pattern.