I think if you have a source of nicotine base, you will be fine.
Flavorings like this were and are used in candy, baking and the like as mentioned. They will continue to be used for those purposes, even if the FDA somehow bans them for e-cig use.
They will still continue to be sold, they just won't be advertised or the use for e-juice inferred in advertising. It's all in labeling and advertising. You may have to start flavoring your own juice, but I could even see companies selling pre-mixed flavor bases for 'candy' that you just add to unflavored juice. I'd be willing to bet many of the companies currently making e-juices, will sell the pre-mixed flavorings instead.
You may have to buy 'candy flavors', but folks will continue to use them as they see fit. There are many
'things' sold with an intended purpose other than what they are labeled.
I think the biggest hit by the FDA will be limiting/controlling and taxing nicotine bases and even unflavored e-juice. They a 'losing' a lot of tax revenue from tobacco since vaping has taken off and smoking is less popular. I'm sure they will make up for this by taxing nicotine bases sold for e-cig use. I mean heck, currently, I can buy a gallon of quality pre-mixed base for around $30. That's over 8 months of chain vaping DL for me. That is $3.75 per month for nicotine. How much is a pack of smokes these days? I have no idea.
Stock up on nicotine concentrate, and you will be fine. I've got at least 8.5L in the freezer and need to quit buying it, but it's SO INEXPENSIVE right now. That's about a 45 year supply for me and I probably won't live more than another 25, lol. I can't imagine how much it will cost/month to vape once the govt starts to tax the nicotine we use. I will probably buy another L or two in the fall when the weather cools down.
Get nic concentrate while you can. You WILL be able to get PG, VG and flavorings later. Flavoring may just be ridiculously labeled. Possibly even sold as food grade 'air fresheners'. Creative folks wanting to make money will figure out how to sell/label flavorings we can use.