This is not Good Bye...

Today is your last day with our project team. I hope that you have made the right choice to move on to do something else more suited for you.

The road ahead is tough, I know, I have spoken to your "future" colleagues, but I believe they will help you. You just have to ask if you do not know, and read more to gain knowledge. After all, it's pre-sales, you are expected to know more than an ordinary engineer.

Take care, you will have my support.

Ps. Just got news that the replacement for you has not be found, and may not be found in the near future...life goes on...