Sept 2022 Update Issue - Hierarchical axis

Since the Sept 2022 update I have issues with the X-axis of my line charts.  Chart 1 shows what the chart looked like before the update.  The chart is showing the results of testing conducted at multiple dates across the past year.  It uses a legend which is the Test Summary.  The data used in the chart is structured per the example in Table 1 (dummy data). 

Since the Sept 2022 update, the chart instead looks like Chart 2 both in Power BI Desktop and the Service.  I've tried turning on/off the "concatenate labels" option for the X-axis, adjusting drill down levels, etc. (see Charts 2 to 4) and I cannot recreate Chart 1.  The chart appears as desired until I add the "Test Summary" field to the legend.

Is there any way I can recreate Chart 1 post Sept 2022 update?  Is this a bug I can report somehow?  Any help greatly appreciated, thank you!

Table 1 - Data Structure Example

Chart 1 - Prior to Sept 2022 Update:

Chart 2 - After Sept 2022 update (default behaviour - concatenate labels on)

Chart 3 - After Sept 2022 update (concatenate labels off)

Chart 4 - After Sept 2022 update (concatenate labels off, Month drill level)