I doubt the BY webspace supports any sort of 'clever' scripting, i.e. PHP. Possibly perl though.
If it did, you could potentially have it do a quick connection on port 80 to see if your site was up, and then send a redirect header to redirect the page. It'd actually only be a few lines of PHP to implement. But it's reliant on the PHP being there.
TBH, get a
proper web host.