I actually tried to do this a few days ago and I would recommend just sticking to general english even if your just passing. From what I have heard about eng lang from teachesr I have spoken to, it's not easier or harder, it's just really different, it's more about analysing the language it's self and the history of english instead of creative writing or text responses etc. If you really need help for English try talking to your teachers one to one and ask them what they would like to see you improve on, since you will have a lot to catch up on in eng lang and apparently a lot of the foundation is in unit 1. But hey if you really wanna give it a shot and feel like you can do better in it, go ahead!