I tend to be paranoid about the main housing o-ring......keeping it closed all the time puts pressure on it.....so I guess you could argue keeping it closed for a long period could increase wear. I store mine open inside a water/air-tight tupperware container.
I suppose worrying about keeping it closed for 24 hours during travel is probably more than a little paranoid....at least as far as the o-ring is concerned.
I would have camera/housing with me as a carry-on in my camera backpack
I always take out the o-ring out and store it separately, lubricated in a zip-lock bag. It never stays on the housing unless it is being used. I use the same housing you do.