You got your sentence wrong. You receive the message BEFORE you see the person through the telescope typing the message, i.e. it takes 2.5 seconds for light to

You got your sentence wrong. You receive the message BEFORE you see the person through the telescope typing the message, i.e. it takes 2.5 seconds for light to reach us from the moon, you would get the message 2.5 seconds before you see the person typing it assuming the FTL messaging system was instantaneous.