Is completely dunking the chain in hot wax better than using a bottled wax lube? Sure. Is it worth the marginal gain over the huge hassle of being prepared to do a complete lubing? No way. The suggestion to bring a new chain was an excellent one. New chains have very robust grease that will last hundreds of miles. A properly waxed chain and a separate new chain should take you for over 5 hundred miles and if you're out to sea for 4 months with occasional stops in ports, you may not get much more mileage than that and if you do, the simple use of White Lightening would be more than sufficient. Just as importantly you may wish to bring along WD40 to ensure you can remove rust if you end up riding on a windy day near the ocean and get sea spray on the bike. WD40 may strip the wax and being able to easily touch it up with White Lightening would be great. That would be my approach.