Perfect Murphy's Law question- you say you take the camper off to storage- that changes it for me.
Totally understand your dilemma: Yeah, most of us have lived with brief dips below freezing at night, but things warm up during the day...And, if you can put an electric heater in it (which I'm guessing you can't when it's in storage), it serves as a little extra insurance (although people will rightfully warn you that the heat may not make it to where it's needed).
But here's the deal...are you comfortable taking the risk that you get an extra bad cold snap while your camper is away?
Blow it out definitely...as to pink stuff who knows- some people cite damage when they skipped the pink stuff.
FWIW, my camper is currently blown and stored for a late October trip. Will do pink stuff afterwards.