Neat. Well, in that time you should come up with a plan to maybe get him some stuff while he's on that 6 hour clock, hell they might even remove trading off to prevent leaching off other accounts for 6 hours (Why I say this? It's 6 hours IN-GAME TIME) so speed mules could be done and you could have a legit 100% safe mule account for weeks or months.
If they don't, you could give him some stuff and go camp lava dragons for maximum magic/prayer gains, important stuff in DMM to get around safely.