Same here. My flight IB 6402 on 7 June just changed from 2 class (345) to three class (coded 346).

Now, surprisingly, this also changes the J configuration:

345 (two class): J from row 1 to 12, odd rows with window seats (A, L)
346 (three class): J from row 1 to 9, even rows with window (A, L) - similar to the A330

Unfortunately, EF doesn't show a PE seatmap, as yet, although it shows availablity in booking classes W, E, T.

On the 346 PE configured bird Y starts at row 21 (row 14 on 345). Both rows are exit rows, with ABJL seats only. So it appears that PE is only taking the rear part of J? Unfortunately, EF also does. lt show the lav location.