Changing address before moving?

[Millu]

I am planning to send update package to london uk.
We have to also send letter regarding wrong spelled last name(sponsors, not mine).
We are gonna move in 3 weeks, can i update the mailing address already?? If i say after 24.01.2011 my mailing address is gonna be ......

What do you think? Or should i just wait until we have moved and change it then?

Thanks alot for your help!!! again