expiry

Can anyone tell me what the shelf life is for the flavour apprentice flavours? Weeks,Months,Years?? Do they even go off? Any input/advice would be greatly appreciated. Thank you> :)

Howdy all.. I have 250ml of 25%vg 75%pg 24mg nicotine i bought from my freedom smokes around 2 months ago... And just received 1 litre of 100%pg 100mg nicotine from the same company.. looking around the bottles ... i failed to find an expiry date. Does anybody know when or estimate of its...