yes when using any sort of medium with nutrients in it you should wait off a bit to kind of let the plant use it up. this highly depends on how much the manufacturer puts in the medium. take for example fox farm. they got ocean forest which i believe is rated for 3-4 weeks , happy frog which i believe 2-3 weeks?, and strawberry fields which i believe 1-2 weeks?
i personally like to go 1 week before the last dated week. so say ocean forest as i tend to use a lot of soil rated around 3-4weeks usually. last dated week is 4 so i will start feeding at week 3. depending how big the plant is will depend on how much i feed. the smaller they are the less dosage i tend to give. once they are big i feed full dosage. i always try to leech the feedings inbetween though giving about 3 waterings with just plain water. you NEED to understand what you are buying. if you don't understand what you are buying medium wise that is where your first fuck up is. figure out how many weeks of nutrients it should last and work from there. some medium contain little to no nutrients added and in those cases you need to feed earlier.