I assume you are growing in a soil mix of some kind. Autos don't need anything like the level of nutrients that a photo does. For example I am giving my photos 6ml per gallon of Old Timers per feeding. In the summer I grow Autos in a poly tunnel and they get what is in the soil and a weekly dose of tomato feed once they start flowering. TBH I normally just use tomato feed with photos, but I have Old Timers that I bought by mistake yhat needs using up, I forgot to cancel the Amazon subscription.
All of those bottles with cartoon characters on the label are purest snake oil, basically when mixed they are just about the same as a regular balanced bottle feed. Advanced Nutrients are known to be a complete rip off.
If they were mine I would give them plain water and for a couple of feeds and then maybe mix your nutes at 50% until the end. Flushing is for toilets. You can tell they are getting too much nitrogen by the dark/shiny leaves, which in turn is leading to burnt edges.
