The ATO ruling seem to agree with what was explained to me by...

The ATO ruling seem to agree with what was explained to me by @gjh regarding Coles Cost base calculation..  This is how I understood it to be..

Example of WES and Coles Cost base calculation..​

	Column 1	Column 2	Column 3	Column 4	Column 5	Column 6	Column 7	Column 8	Column 9	Column 10	Column 11	Column 12
0	In paragraph 68 of the Class Ruling, the Commissioner accepted the VWAP of the Wesfarmers and Coles shares to be as follows:
1	VWAP $ Relative Market Value (%)
2	Coles ordinary shares		12.8459	28.91%
3	Wesfarmers ordinary shares		31.5848	71.09%
4	TOTAL			44.4307	100.00%
5
6	Wes demerger Coles	28th Nov 2018	No of shares before Demerger	Cost per share before demerger
7			WES	1000		28.026
8
9
10	After demerger, ATO ruling new Cost		New Cost
11			WES	1000	71.09% of 28.026	19.9236
12			COL	1000	28.91% of 28.026	8.1023
13

The date of acquiring COL shares for CGT purposes is deem to be same as when WES shares were purchased.