Day 1 give them a chance. Gardmoemen have many challenges wnen Fornebu closed overnight yet did anyone worry some weeks later when things settled down.
Think what its like when you move house and you planned that yourself then multiply that X fold and you might start to have a slight understanding of the logistics involved.
Could they have moved T1 operations first then T4? Well no because the integration is planned for one terminal.
BA and BAA have done many things to be annoyed about but give the troops on the ground a break...