"use within xx days"

[Ivysaurus]

So I keep having a lot of food waste due to jars and packs stating use by time frames. How strict do you follow by these?

A pack of cooking bacon 'once open use immediately' - why? It's been in my fridge a week so is it no good now.
Jars of pickled things/sauces 'once opened use within 4 weeks' - why? What happens if I just keep them open til they're used up?

Jar of pasta bake sauce 'Do not reheat' - it's only pasta (and maybe meat) in sauce, can't i freeze a portion once cooked and reheat it?

What about bread bought from bakery counter at a supermarket, I'm aware they are cooked in store from frozen, so can I slice and freeze these loaves?

Trying to fight waste but adhering to all the rules it's too hard

If it smells good, looks good and tastes good, it probably is good!

Obviously use some common sense - eg stick to the rules with fish, raw chicken etc.

Opened bacon tends to be fine for a couple of days.
Pickled things will be fine for ages.
Pasta sauce is fine to reheat. Just make sure it's hot all the way through.
Of course you can freeze bread - we do it all the time.

As long as it doesn't smell/taste funny, you'll be fine in most circumstances.

I'm the same as you op I'm a stickler for the rules, it scares me to deviate from what I'm told haha!

It's such a shame that there's so much food waste caused by dates on food and the seeming lack of common sense nowadays.

Food doesn't know what the date on the packet is, it doesn't spontaneously become poisonous on the stroke of midnight on date on the pack.

Use your senses to decide as generations before us did. You wouldn't eat something mouldy because it was still in date so don't throw away perfectly good food simply because the law says it has to have date on the pack.