Elwood mentioned both getting back on a smaller bike and taking the BRC over again, certainly one way to go. However if getting hold of a 250 isn’t an option or isn’t your way of approaching things I’d recommend taking the ERC rather than retaking the BRC. In actuality the curriculum of the two courses isn’t all that different, they just assume you know the basics. The reason I recommend the ERC is that you take it on your own bike. For me the confidence that came from completing the exercises on my own bike was invaluable.