MuscleNerd just warns Apple is taking process to block the SAM unlock via his twitter. If you wants to save your unlock, you should backup your unlock ticket right now!
"Looks like Apple's currently fixing their activation servers. But the good news is that previous tickets gotten via SAM trick still work.
what it boils down to is an incorrect assumption on the part of the ticket server, which is why it was so quick to fix
for the next few hours, trying SAM on new SIMs will probably be hit or miss, but eventually it will be all "miss""
Here are the tutorials you should need: