At first, we did not know if we should come back. Our memories of you were, after all, laden with guilt. We did not want to face you, even when we knew that our neural serums had erased your every recollection of us.
We considered broadcasting to Earth via your television or radio devices, but ultimately decided that our message will be much more believable if we simply came to Earth ourselves. This way we can deliver our news in person, through that curious adaption you call "speech".
You see, our story is similar to that of the lands you call Britain and Australia, the former penal colony. Our institutions were being overrun with your kind and we could do little to help your affliction. We decided to colonize Earth, teach you a few necessary skills, and then leave you to decide your own fate.
Those among us who took pity on your sad state have been monitoring your efforts at self-treatment. At first, the evolution of your crude languages was of little note, but your forms of communication quickly grew more complex. Although surprised at your ingenuity, we assumed that you would perish quickly, forever unaware of your true potential.
You must understand: we did not wish to leave you this way, to abandon you. Sending you to Earth, condemning your minds to generations of torment and decay was not what should have been done with you. Unfortunately, there is no undoing your impoverishment, but we did not know then what we do now.
Since the day that our scientists discovered how to rectify your deficiency (about 6 months ago by your calendars), we have debated whether we should try to cure you or simply leave you alone until your inevitable extinction. However, the ecumenical ones amongst us prevailed, and so we decided to give you what aid we could. In exactly 3 months, then, we will return.
We will come back to Earth with our most talented surgeons. For those who wish to undergo the corrective procedure, you should know that our doctors expect it to be quite painful, as we have not yet perfected the crucial surgical techniques. Hopefully though, many of you will summon the courage to correct your heinous disfigurement and rejoin our community.
And for those of you who do not wish to repair your bizarre lack of telepathy, good luck to you. We are sorry for what we have done.