My HTC Trophy today got the update notification and the phone is unlocked.
Another thing to force your phone to get wp7.8 update there are some steps you should do it :
1- connect the phone to the laptop
2- open zune and then when the device is connected go to settings
3- click on check update in the device settings
4- next after you click on it disconnect you computer from any internet connection like your wireless or LAN
5- immediately you will find your phone says "there is available update"
Another thing to force your phone to get wp7.8 update there are some steps you should do it :
1- connect the phone to the laptop
2- open zune and then when the device is connected go to settings
3- click on check update in the device settings
4- next after you click on it disconnect you computer from any internet connection like your wireless or LAN
5- immediately you will find your phone says "there is available update"