New Premium Economy coming to Westjet.
 

Unfortunately most of the story is password protected and I can't find details elsewhere.

WestJet details 737 premium-economy retrofits | Aircraft Interiors content from ATWOnline

WestJet’s premium-economy trial has paid off, convincing the Calgary-based LCC to launch a fleet-wide retrofit that will see new, larger two-by-two seats replacing the current three-by-three test configuration that uses a blocked middle seat. The Canadian carrier plans to start the modification work on its Boeing 737 fleet late this year and expects it to take about 18 months.

This may be seen as the next step towards joining an alliance, so they can have J-class passengers connect to/from 2x2 seating, which closer to mainline J on (say) DL.

You will be blue as a Smurf holding your breath for this to actually happen. Any airline that buys new 737 and puts in new 3X3 seats is not serious about suddenly going 2X2 in a year across the fleet.
Of course once the strike happens they will have lots of downtime as people attrite in droves to whoever is not on strike, so it might be a good time to refit to what they should have been doing for years.
With all entertainment via wi-fi of late there must be tens of thousands of seats with power plugs only (which is all they need) down in the Arizona boneyards available for the asking.

Proof will be what happens to the 7M8s arriving this year and next. If you start seeing those planes with 2x2 seats, I'll believe it. I don't know why they don't, it's not costly to put the seats in, and if the middle seat is always blocked why bother?

I'm glad to hear this, but I'll reserve final judgment until I see the price.

I imagine two rows of four seats.

Seat width. Any airline with a "premium" offering that is just a blocked middle seat has totally missed the mark (and that includes virtually every European airline).

This would be great news!

With that, I wonder if they'd make any other changed to bring this more in line with a J offering? Like maybe a curtain divider? Lounge access? Allowing only plus pax to use the forward lavatory?

Also reported on One Mile at a Time:
https://onemileatatime.boardingarea....ess-class-737/

Nope. We've been given details of reconfig which includes:
- Adding a second lav in aft of 600s/700s
- Ovens
- A "skyDivider" between "Plus" and Economy

FYI

They could always do what Alaska does. If you are seated in the Economy cabin, you can use the front washroom, but you have to wait at the Economy/Business dividing line until it becomes free. That gives Business passangers first chance at the front washroom but handles the problem that the 737 is a crappy aircraft from a width perspective. (It is a nice aircraft from other perspectives).