I noticed this issue in a pbem when my Entente opponent promptly vacated the entire region early on with no real reason to stay.
It is a serious faux pas having no incentive for the Brits to hang on to Basra especially (Kuwait less so but to keep it simple both are a part of this solution). This was an absolutely critical oil area and the main reason the Brits made holding the area a strategic focus during and after the war:
https://worldview.stratfor.com/article/ ... ttle-basra
What I propose is an honour agreement: when either of these locations falls to the CP the Western Entente must asap execute a gas attack on a clearly unimportant enemy-held location with no land unit attacks a part of it, thus incurring -1 NM. Once captured by the CP, if the Brits manage to take either or both back, the CP has to pay the same -1 NM gas attack penalty. This back and forth has no limit in repetitions.
[And may I say as a long-time published scenario creator and editor it's a real shame this AGEOD game system does not have an editor included outside of arcane code manipulations that are difficult to ferret out on the forum and elsewhere... open it up finally and let the game grow further please.]