På fråga:
1: 1 år är minimum.
2: Goggle på Blacksn0w gav detta:
Citat: It appears some users are having wifi issues. Try a “Reset Network Settings”. If you are still having wifi issues, see here. They don’t appear to be caused by my software. Also, this just enables custom MobileConfig files. To fully enable tethering, go here on your iPhone and download a MobileConfig file for your carrier. Watch out for carrier fees for tethering.
If your ipt2/3GS/ipt3 is rebooting into recovery after running blackra1n, this isn’t a bug. It’s a feature. You need to run blackra1n every time to boot it. This ‘feature’, called tethered jailbreak, is enabled by upgrades Apple made to the bootrom and the fact ipt3 uses nand flash.