Grouping by a field

Hi All,

I have a table structured as follows. 

I want to create a start (Create Date) and end date (Last updated Date) grouped by tiers as follows -

however I am getting

by using Max and Min dates for Event date and putting tiers to rows. 

Will need some advice on the above. Also, some cases have multiple tiers and they can start for tier 2 or tier 1 or even tier 3.

Thanking you all

Regards,

RS