Horizontal Middle Data Sequencing

G'day,

I have a numbering convention that needs to be adhered to and i am able to perform the sequencing vertically since its the last two digits that need to change vertically, but allowing the 3rd set of digits within the cell to sequence horizontally without changing the last set of digits doesn't seem to work for me. The example data is as follows:

01.01.01.01 01.01.02.01 01.01.03.01
01.01.01.02 01.01.02.03 01.01.03.02
01.01.01.03 01.01.02.03 01.01.03.03

When I autofill vertically its fine but it wont let me begin the first cell in the row to sequence horizontally.

Any insight or solutions are greatly appreciated.

Would you be able to show me how that works within the excel sheet I attached please?

hmmm, It might be me but I've tried that and doesnt seem to do what I'm trying to achieve.

Thank you so very much everyone, i tried both and they worked as needed. Muchly appreciated!