Every branch has its own style, dynamics, and customs. No matter how many years' experience the new arrival may have with the SCA in other places, he cannot know the way people like to play to game in every shire. Just because he knows how to help run things where he came from does not mean that he knows enough to help out in his new home. He has useful skills but has to learn how to apply them to the local situation. In a similar vein, it is unreasonable to expect a branch to put its confidence in a new arrival immediately, no matter how much experience he has elsewhere.
Most branches have limited resources - offices, autocratships, regular meetings, money, etc.
The members of the branch want to get the most out of those resources, and they don't know a new arrival well enough to be sure that they can entrust their resources to him. It is more than a little presumptuous for a new arrival to sweep in and expect to have a major role in alloacting resources until the rest of the group gets to know him. They don't know you at all. Your awards and past accomplishments will carry some weight if you make gentle suggestions, but it is self-deluding to expect to take up here exactly as you left off in your old group. Part of the problem is simply a change of vocabulary.