Columns headers that change every month

Hi ELToninio ,

Greg_Deckler Thanks for your concern about this case!
Have you solved your problem? If not, can you explain to me how your data is changed when months are changed? Do you just overwrite the previous month's data, or do you just add this month's data to the original table?
The operations you perform in Power Query are memorized, i.e., when your original data changes, all the data cleansing, data transformations, etc. you have previously performed will be reapplied to the new data. 
If your data is directly overwriting the previous month's data when the month changes, then you just need to refresh the data source and Power Query will automatically promote the first row as header.
If your new data is new, make sure that the new data is added above the old data and not below it, so that after refreshing the data source, Power Query will promote the row as header of the new data.

Best Regards,
Dino Tao
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