dynamic named range relating to cell values

Is it possible to create a dynamic named range relating to values within a specific column?

In the example worksheet I've attached the range would be depedant on column D.

i:e each range will start with the first group of matching numbers and end with the last.

All the date in that column will be in numerical order.


I'm not sure if I require a macro to do this or if it is possible to adapt the formula below?

=OFFSET(MySheet!$A$1,0,0,COUNTA(MySheet!$A:$A),1)

Any help or pointers in the right direction will be much appreciated