I’d imagine their stock control is all over the place at the moment - things probably aren’t actually out of stock, they just aren’t 100% sure what they’ve got and where and so are limiting orders to items they are confident that they have and can deliver.
I’d personally be waiting a few weeks until things settle down, and they’ve done some stock counts and got themselves straightened out a bit.
But it’s nice to see that they are going in the right direction at last.