It has popular support. But does it have constitutional support? That’s what a state appeals court is trying to figure out as it weighs the legality of a plan to limit legislators to eight years in office. A 1st District Appellate panel heard arguments last week in an expedited constitutional challenge to term limits and could rule on the matter any day. The ultimate decision on the plan, which also seeks to change the size of the House and Senate as well as the number of votes needed to override a …