As I noted in my previous post, if the EEC is healthy and the only reason it's in Alternate mode is due to manual selection of the mode switch (e.g. because the other engine EEC did have a fault and auto-reverted to Alternate), Normal mode can be selected at any time by simply re-cycling the mode switch.
That being said, if you want to get back to Normal mode, there is little down side to simply cycling the mode switch to see what happens. You're not going to hurt anything, the only real draw back is having to retard the throttle to a mid position before you cycle the switch (the short time loss of thrust might be undesirable if you're operating single engine).
BTW, I was involved in the original development of the 777 engine control/EEC - I do know what I'm talking about...