Ignore the '6 hours' bit. Nobody (apart from the perpetrator/s) knows how long the attack will last.
Only 1 IP address is affected, and it's the one that handles all *.net84.net addresses.
If you park a domain name (even a free one like .tk or .co.cc) on your account and use the control panel allocated IP, you will again be able to access your site.
Free web hosts are all much of a muchness
. You stick with the one that upsets you the least.