Hello! I often switch between my 3G iPhone and a 4G Galaxy Nexus (I'm a developer, but I'm too cheap to activate two separate lines). I've heard that as long as I switch back to the 4G phone by midnight ET, the SIM card won't get marked as retired. So, if I need to use the 3G iPhone, I switch using the Verizon website to the iPhone in the morning, and then switch back to the 4G Nexus before midnight.
This has been working fine, but lately when I switch back to the 4G Nexus, my account will be marked "Order Pending". When that happens, my account gets frozen and I can't switch phones until it goes away. Sometimes it lasts quite a few days, and I can't switch to the iPhone.