Mike M. Volokhov wrote:
> Some of our developers are professional consultants. In case you do need
>   help, you can sign them up at short notice or for bigger projects.
> 
> Is that text (second sentence) correct? If yes, could anybody explain
> it for us, please?

That's my rendering, although I'm not really satisfied with it.  The fact
that it's not clear to you is reason enough to rewrite it.  

	> In case you do need help ...

If you don't find things as easy as the previous paragraph says ...

	> ... you can sign them up ... 

You can hire them [the consultant-developers]

	> ... at short notice or for bigger projects."

No project to big or too small (implying that larger projects cannot be
taken on at short notice).  

Perhaps something like this, instead:

	"If you find your project would benefit from an expert hand, you'll be
pleased to know that some of our developers are professional consultants. 
They are available for projects large and small, often on short notice."  

--jkl