Arriva hasn't got anything live on their website but it has been announced via the local press about their intentions stating
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Clearly Arriva has given out some information else it wouldn't be in the news. Nothing should have got to the papers until it was confirmed the depot was closing and any replacements were put into place. It took Chalkwell what... 6 days to take up the services. If the news had waited 6 days, a lot of public upset would have been saved. Similarly if the situation on the 367 was explained, that would have sorted things out but the half information and half statement which went out to the press has just caused public upset and confusion.
I think you have the order of things mixed up. Arriva didn't announce anything publicly themselves, as the story makes clear further down from the bit you have quoted. Nor should the fact they have (appropriately) told Kent County Council (KCC) anything mean they should be the public eye now, for something that won't be happening until July.
If a driver tells a customer, a customer goes to the local press... what is supposed to happen next? Ride roughshod over the consultation, such as it is? The paper say nothing until the consultation is complete? Leave it all to Facebook? What are Arriva meant to do when contacted? Lie?
The only "public upset" caused is by half-stories in the local press, where they have immediately jumped to conclusions that were unlikely to ever happen, and commenters who still think Arriva have a "contract" to run the buses should have it taken away from them waffle on for paragraphs that make no sense. The "Save our Buses" campaign is, and always was, totally unnecessary - the classic thing a local paper comes out with. If KentOnline had done their research and presented the actual situation differently (namely that KCC would likely ask operators to step in, or provide some sort of tendered replacement, and that the chances of there being no bus service at all, in any shape or form, would be very slim), no "upset" would have been caused!
The situation with the 367 is different, as that is a tendered service anyway. No announcement could possibly be made on that yet: as KentOnline would also know if their reporters had done a modicum of research!
42 days before 16th June is 5th May, so it wont be long
As Chalkwell have announced not starting until 12th July, might that period now be extended? I'm not sure what the rules are about the local authority consultation stage in a situation such as this, where the local council are already involved.