Using a proxy would work but it would slow the download speed quite a bit and finding good working proxies is quite difficult, especially fast ones. They need to be highly anonymous proxies to fool RS. If anyone else has used the same proxy, you would have to wait like you do with your own company IP address.

Trying turning the clock back on your system to every 15 mins/30mins, heard it resets the time as RS go by the time on your system. Not guaranteed to work as that's what i've heard.

You could always reset your changeable IP on the router, there's even a program for doing that if I remember correctly, although it will disable your internet for a few seconds every time (depending on the router) and this is by far the best option you have other than buying a premium. Other options are just not practical enough.