I can answer #2. The SFA esters do not go bad as far as has been tested. The rest of the product is vitamin E, which also has very long shelf life. However, FDA mandates that all liquid products be advertised with no more than 12 months of shelf life. So, it's up to you to decide if you want to use it if it has been more than 12 months since buying.
Thanks Haidut, can you let me know the absorption rate when applied topically? I remember the last time I used it my teeth were very sensitive, so I would like to go the topical route this time