Slitherine

I set up a game in which I played an Astra Militia faction as one of two factions of Team A. The other faction is a AI Astra Militia faction. Team B consists of 3 Necron factions.

My AI Astra Militia faction is way ahead of mine in research and production of units. It has produced several baneblade tanks and my faction isn't even up to researching baneblade tanks. Also, the AI faction has out produced mine since the start of the scenario. I set both factions to the easiest difficulty setting of War General. I was playing the 1.1.12 update and will now update to 1.1.13.

Does the AI have a built in advantage in research and production over the human faction?

The only advantages are the ones you give it. The game setup says if you're giving them a bonus. The AI is now pretty good and will outplay a human new player fairly easily on equal settings so you may need to give it a handicap while you get to grips with the game.