Re: Possible trip next weekend
The thing with the refuge is if you want to fish there at night you gotta be on before sunset, the inbound gate closes between sunset and sunrise.
Also, if I'm not mistaken Cranes Beach is essentially at the southern end of Plum Island, just across PI sound. I've never actully fished it but I can't see where it would be all that different than PI, it's pretty much the same stretch of ocean. If there's any significant difference someone will probably chime in here and let you know.
Good luck, last Sept/Oct were great. This Sept was slow for me (only one good night), hopefully Oct will pick up.