Summary / Title: [PC/Steam, v1.0.1.59] Knights will become buildable again after researching Insurrection Theory

Description: When both Dragoons and Knights are already researched and the player has the required resources to build the Dragoons the Knights unit will be removed from the buildable unit list due to the Dragoons are a direct upgrade to them. But after researching the Insurrection Theory technology in the contemporary era, the Knights will become buildable again if the player doesn't have the required resources to build a Helicopter Gunship unit. In this case, both the Dragoons and the Knights unit is buildable and the tooltip shows that both can be upgraded to the Helicopter Gunship unit. The Knights are no longer upgradeable to Dragoons due to it has a better (Helicopter Gunship) upgrade. This problem will go away if the player gets enough resources to build Helicopter Gunships because in this case, both Dragoons and Knights won't be buildable anymore. This bug won't happen if the player has the required resources to build the Helicopter Gunship when the Insurrection Theory research is finished.

Steps to Reproduce: 

1) Get both technologies for Dragoons and Knights

2) Research the Insurrection Theory technology while you don't have the resource to build a Helicopter Gunship unit

Reproducibility: 5/5

Expected Behavior: The Knight unit shouldn't be available after a player researched the Dragoons and have enough resource to build Dragoons. 

Attachments:

Buildable units after researched the Insurrection Theory technology