I routinely keep it in the fridge for quite some time after opening. I'd smell and taste it and if it seems fine, it is.

I have a bottle in the fridge that’s been open for a month. It says it’s only good 3 days after being opened. It has a ton of sugar in it and it smelled fine (didn’t think to taste it). I used it in a recipe (for me, not for holiday guests). I’m not worried at all but wondering if anyone else has experience with the shelf life of this ingredient. TIA.