no post-II As. still waiting on two schools for final decisions. Currently on WL at 3 T10s and 1T20.

Anyone have any advice for getting off WL? I know schools probs dont reevaluate till after April 15 or 30, but I'm wondering if anyone knows of any success stories in years past. My top choice doesnt take intent or interest letters, so I am planning on writing an intent letter to my #2 school on may 1. Other than that, I'm planning on sending updates around april 15 to every school while briefly expressing continued interest. does this make sense?