If you are going to have the dealer do it, the only advantage I can see with waiting is that you may decide that you are happy with the bike as is. If your mind is made up might as well go for it.
Your dealer may be reluctant, but it is much better to match bore your cylinders to the particular set of pistons then just buy the replacement cylinders. Cheaper too. Make sure you go with the flat top pistons. Make sure they use the -A SE intake kit, as opposed to the old version.