Is it possible to transport units (via Overlord) in the Heart of the Swarm campaign?

Playing through the Heart of the Swarm campaign, I noticed my overlord options were limited. Is it possible to use overlords to drop units during the Heart of the Swarm campaign?


In the campaign, the Overlords are just basically flying supply depots. Thus you can NOT transport units in them.


I am positive you can not transport using overlords. I did read on a web page that you can, further research has told me that it is impossible.