Taking several examples from the community, I made a form in which I had a repeat section with several related lookup fields inside.

If on line 1 of the repeat section you selected one value in the lookup A, the lookup B was reloaded with the filtered values. 

Line 2 of the repetition section was independent. You could select something in the lookup A that did not interfere with the line 1( Nothing changes on line 1)

This was working and in production.

Now, without modifying the form, line 1 works fine, but as soon as I add a line, I lose the values (already selected) of field B in All the rows

Example:

Filling first line 

Try to add new row: 

This is normal behavior or a failure in the last release???