WDRR delay for parade

I seem to recall reading that the train is delayed or held at Main Street as the parade is ending to allow the floats to cross the track back to their holding pen. Is my recollection correct? If so, does anyone have an estimate on how long the delay is? I have FP+ for the parade (Town Square viewing) followed by a plan to see Under the Sea. I wanted to take the train around to save some walking… Am I going to be getting in a long train line to do it because of the delay?