I have been on 3 different FRC teams and 2 different FLL teams. The teams I participated on for FRC were 1126, 229 and, 1930. For FLL I was on the Webster Lego team and the Wellsville Lego team.
In the last three years of High School, I was on the originating team of 1126. In 2005 i graduated as multi champion and very proud. The following year i attended college in Canton, New York. (Basically middle of nowhere wayyyy up north) Clarkson University was only 10 minutes down the same road, so I was able to be a College Mentor on the 229 crew. It was a lot of fun to move up to the College Student role and be on a new team. The course I was studying was only a 1 year certificate. After that was done, I moved onto another college closer to home and tried to start up a FVC team at college. Due to no success I could only help with a local Lego team that my professor requested me to participate on. It was a great honor to see the kids every meeting, and how proud they were at the competition. This following year I moved back up to the FRC level and was a College Mentor on Team 1930. A hometown team that goes under the radar. I had the opportunity to go back onto the 1126 team and i was honored. I choose not to participate on their team anymore. It was not from them telling me to go away, I am always welcomed at any meeting. They even donated numerous materials to 1930 through me.
I only choose to move on to a different team for one reason. Knowledge. I see that 1126 doesn't need my knowledge and probably will not ever again. I wanted to give back to other teams with my knowledge and see what comes out of it. I was very proud what 1930 had produced this year. At the start of brain storming, the kids wanted to go for a ball herder ONLY. Due to their experiences of low level robots and failures. They were skeptical to the newly developed mentors ideas and did not want to hear it at all. Once the designs came into real life, the sights and faces of the kids were amazing. I felt as if we changed the way the team looks at FIRST robotics now and that just makes my day. With all three teams I was on, I have seen students come back to mentor once they graduate. It is a honor and should always been seen as your first 'home'.
With all this reading, I suggest a few things. Look into your High School's program, look into other teams. Does your HS need your help still? Does other teams need your help more? Where will you fit in the most.
Hope any of this helps.