но как только....

What does it mean?

e.g.
но как только будет свободное время, я напишу...

But as soon as...

But as soon as I have free time, I'll write... (to you)

P.S. I mean it could be "to you", but it's not necessarily so.

Ok. Thanks :)

Another Q:

Кому я нужен!

What does it mean?

It means:

Who needs me? Who cares about me? Nobody will harm/hinder/disturb me.