I'm currently pondering a new commuter myself, after my amazing power (not) somehow sheared the drive-side crank through the centre of the pedal threads last Tuesday!
The 20" Marasa is certainly available to collect here in Southampton, with a week for Halfords to get it ready. Shame it's £450 rather than the normal price of ~£320 before lockdown, but the RRP had to increase sometime, it's been than sort of normal price for 5+ years.
The Subway2 is alright for £350, very solid frame and hydraulic brakes on the new version. However, personally, I don't need/want a 27.5" wheeled bike, I have 23-60mm 700/29er tyres.
I'm kind of drawn to the new £400 Carrera Vanquish, even though it has cable disc brakes and only the small frame is availble right now near me at least. This might also be partially down to the enlightenment of seeing how much faster my "nice" road bike has been on the commute since Saturday compared to my fatbike that was essentially a 29er hybrid for most of the last ~4.5 years.
For £1k, the incoming new Boardman ADV 8.9 looks great with GRX hydraulic brakes.
However, just like if I was to start using my road bike commutes permanently and get something else "nicer" in due course, I'd be terrified of locking it up anywhere if say I wanted to pop into a food shop.
I've got 11 days off now, so a bit of time to think, but my sensible head says reserve a Marasa on "click and collect" and use 10% British Cycling discount when I collect it. With a few changes, I should be able to easily get it down sub 12Kg and I'm hoping it might have clearance for 2.35" tyres, as I've a pair of G One Speeds and Vee Speedsters with a fairt bit of life left in them (I'm very confident my 50mm Schwalbe Century pair will fit). Great gear range with 26/36/48T crankset and 11-34 cassette plus hydraulic brakes.