Is it always like this? Might the wording of an order on any particular occasion perhaps allow any airborne flight to complete its planned journey, with the aircraft then grounded upon landing? I can't immediately see how to get hold of the CAA's actual order, rather than the press release.

They're not going to. I'm sure they already have.

I agree that it could be either way. But an operator granted permission to continue and land might not even want to do that - and be confined indefinitely when they they could abandon the sector and return to base and continue in use.

In any event in about an hour it will be an irrelevance as the issue will have passed. The few of them that are in the air and headed this way will have landed or gone away!

Of course. But each operator would then have the option to take its passengers where they expected to go - particularly if that specific aircraft was in any event returning to base. Other operators could decide whether it would be better to do that, or to divert and then re-route the stranded passengers. And, of course, some might take a guess as to whether a one-off exemption for a ferry flight of a stranded aircraft out of the UK might later be given.

Except any that are enroute from the USA or Canada. Both Norwegian and Air Canada have used the type to the UK. They may not have the fuel to turn back.

Looks like the're going to let flight already in the air enter UK airspace to land as BY485 Marrakesh - Manchester is now over UK air space. Two Turkish Airlines flights still flying to UK (Gatwick and Manchester).

It would be rather barbaric to shoot them down rather than allow them to continue.

I wonder if the Turkish aircraft will be allowed to leave?

DQ-FAB, Fiji's Max8, was enroute to SYD from NAN when CASA barred it. It landed at SYD but tomorrow morning's departure has been cancelled. I am not sure if they will be allowed to ferry it back to NAN empty but of course it has consequences if they are not allowed to - parking charges for a start, and operational aspects (e.g. operating to where they are still allowed to).

Looking at that situation illustrates the possibility that it might be in their interest not to land in the UK if the fuel allows, and they are short of aircraft and they are intending to keep using the aircraft in the meantime (obviously with the exception of UK-based aircraft).

Norwegian is grounding its fleet of MAX, not just in the UK but everywhere.

https://media.uk.norwegian.com/pressreleases

I am surprised France at the very least has not jumped on the bandwagon, with their interest in Airbus.

Norwegian have 110 B737 of which only a few are max.

As a statement of the glaringly obvious ... Boeing seem to have created a global aviation disaster! I wonder if the airlines have any comeback on this ... although I doubt it.

EDIT ... comment from PPRuNe ... “In the event of a quality failure of similar magnitude to the 787/RR issues then Boeing at the end of the day...” Ouch!

But the increased automaticity allegedly involved does seem to suggest a degree of overcomplication to what was, once, a relatively straightforward aircraft to operate.

Norwegian Air Shuttle has 8 MAX, based in Scandinavia
Norwegian Air Internation has 9 MAX, based in UK and Ireland.

No clue where they currently are.