Why do major labels vacillate?

If you think that a curious title for a post then I shall expound.
It is no secret that The Shires' début album 'Brave', dropping soon, has no known album artwork as of today. Or at least that is the catch-all position that amazon,com and amazon.co.uk is currently displaying. I have to say that, at this stage in the game, that is rather disappointing. The duo is signed to Decca in the UK and Universal Music Group Nashville in all other markets (the first ever UK act to be so). Be that as it may the labels still can't sort the album artwork such that amazon.co.uk or amazon.com can display it. This, in marketing terms alone, is really rather pathetic. No wonder that the independent labels, that can react fast, are running rings.
Be that as it may...

It is still likely an LP that will have an impact. It won't be the only one.

On the other hand apparently small and insignificant labels can insinuate themselves, and thus also their artists, into the consciousness of music fans seemingly without any fanfare at all. Sometimes emerging under the radar, and then staying there for a while, has advantages all of its own.

Particularly when pop - slightly old-style West-coast pop - is concerned.
Any influence and none, its just your ears that decide that in the end.