移民局网上写的：
Non-U.S. Citizens
If you have moved, you need to follow two different steps:
Step 1: File a Form AR-11 (This changes your address in our master database.);
Step 2: If you have a pending case, you must also file a Change of Address online or call our National Customer Service Center at (800) 375-5283. (This changes your address for the specific application you have submitted.)
Please note that if you are a non-U.S. citizen and you have a pending case, you must complete both steps to make sure that you comply with the regulations and so we can reach you at your correct address.
====问题：STEP 1 和 STEP 2 有何不同呢？STEP 1 是要把表PRINT 出来，填好了邮寄过去是吗？STEP 2 就是ONLINE 改或CALL，这个我很明白.请指教，谢谢