I think if you follow some straightforward instructions, such as "Mindfulness in Plain English", by Bhante G. (recommended by Pink_Trike) and try to not have any particular expectations of what will happen in your meditation you should be fine. If you go into the retreat with the idea that you are there to learn, not to judge the instructions against what you've been doing, but with some practise and discipline in sitting watching your breath that would likely be an advantage, I think. And presumably the style they teach at the Bhavana Society is compatible with Bhante G's book. You might consider reading and listening to some of the other resources there.
I'm not personally that familiar with Bhante G, but I did read Mindfulness in Plain English a while ago and I recall it being good. And many people recommend it. Different teachers have different approaches to beginning meditation, so in my view it's less confusing to just take your advice from one (reputable!) teacher, or one group, such as the Bhavana Society. It's not that the other teachers are "wrong", but they may emphasise different things, perhaps in different orders, so it can become confusing...