Also adding my congratulations .
And I agree with all the advice here .
Keep her off school as long as possible. Ask yourself how long you would want to take off work if your husband died and you had to move home - would a week be enough to adjust to all that ?
Of course it's an incomplete analogy because this child will not just lose her family and her home , she will lose her school and all her friends as well.
Also go easy on the room decoration so she can choose most of it herself. Most 6yo will have an opinion , she may like cars, dinosaurs, fairies or fire engines. You can always just paint a neutral colour and get a plain blind and add curtains / duvet / rug etc when she's home and decides what she wants.
I know it's hard because you have waited so long to be parents and I'm sure you've had fantasies about a cute nursery etc. But you need to think about what you would like in her situation. What would make you feel most at home if you were abducted by aliens ?
One reason adoption is hard is that it starts from a point of loss for everyone involved, so it's very different from giving birth to a baby. Naturally you are very excited to finally have the child you have longed for. But you need to tune into the fact that it's a great loss for most children to lose their FC . And it's very hard to make one attachment while grieving another .
You job over the next months will be helping your DD work through all of this, as well as dealing with your own losses and adjusting to being parents. And it's OK to allow her to have contact with FC ( if she wishes), regardless of what SW say.
I'm sorry if this seems depressing and I don't mean to rain on your parade. But I want to be realistic about what's ahead so you can prepare yourselves for the tough bits as well as how wonderful it will be.