The election rule is that residents can have one sign per open board position in their yard with the proviso listed below. Last year everyone could have up to two signs as there were two openings. The year before, everyone could have three because there were three openings.
If the sign has the 3 candidates on it then that is all that can go up.
If you have an individual sign for candidates then you can put up to three signs as long as there is only 1 sign per candidate.
In other words you cannot have 3 signs for Candidate A, or two signs for Candidate A and one for Candidate B. You would have to have one sign for Candidate A, one for Candidate B and one for Candidate C.