B737 N1 Limit
After TOGA is pressed during a takeoff roll at 64 kts the auto throttle will go into throttle hold. During this time power is removed from the auto throttle therefore the auto throttle is basically inactive therefore pressing N1 will not accomplish anything. Throttles can be repositioned manually to full takeoff power if needed any time throttle hold is annunciated.
At the completion of 18 second period and above 400 RA the autothrottles annunciate Arm; the autothrottle is now ready to accept commands.
Pressing the N1 button will allow the auto throttle computer to set climb power, this is the correct procedure for selecting climb power.
If MAX Continuous power is needed due to an engine failure this is selected off the N1 page.
I hope this helps you.