lol Eccles - you'd be horrified at me. I had some chicken thighs which I forgot about and they were a day past their use by. So I stuck em in the freezer. If they ming when they have defrosted, they are going out. If not, I'll cook them.
EHO guidelines are 24hr to defrost and cook within 48 hours. Once cooked and cooled they then have a life of 3 days. Then you can put them in the freezer. Defrost them for 24 hrs and then get another 3 day life out of them. Or alternatively just give them a good sniff and if Ok then they are Ok.
Best before and use by are totally different. Use by is generally fresh things. Best before is dried food, canned food etc. I can't speak from experience but during the war many food stuff was canned and people were told it would last 20 years. This included cheese and cigarettes.
Of cource they will be Ok to cook tomorrow. If they have been frozen fresh once defrosted they could keep up to 4 days. The dates of food have nothing to do with if they go off. It is a system the supermarkets use to rotate their stock. All prepacked meals like Sweet and Sour Pork/Chinese and Indian Curries will keep at least another week after their sell by date.
I had some rice I cooked recently which had a sell by date of 2006. It was perfect.