Formula in M code to get different comments by finding deviation of batches used in Sales Table.

[ASG25]

I have table called "Sales" as below, In this table i already fetched batch index from day wise available stock table by merging two tables. 

I want to find FIFO deviation of batch which were used in sales table and as per Index marked ("Index ID of Stock as on Bill Date") for each batch by creating new column same as per last highlighted column in sales table with comments.

hope it is possible to find FIFO deviation in Power Query?

Appreciated in advance!

[lbendlin]

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