If you are on JL44 you are on a 777-300ER, if you are on JL42 you can be on a 787-8 or 787-9. There has been some random reports on 42 getting the 77W as well, but it seems to be random cases, and nothing officially scheduled.

The good rows on the 77W are 23 and 45. Though do be aware that the middle section of both are also bassinet positions. Though 45 seems more commonly used for this.
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18 and 45 on the 787-8, bassinet is 46 here. Row 45 for the 787-9 with a bassinet row in 46.

Other seats are pretty much the same with 34" pitch and 3-3-3 on the 77W and 2-4-2 on the 787. The 77W does have a single 2 seater in row 27 right in front of the lavatory though.