I can help you #[1]
When do you want to get notified?
Discussion
I did something check https://ntfy.sh/btctxfee
That must be pulling data from queue and not current block right? 
Yup. It’s guessing what will happen for next block by assuming miner has same mempool and desire to maximize fees collected.
They also compare the blocks that occur to the theoretically best block the miner could have constructed…useful for speculating on censorship or out-of-band payment for blocks space.
You are right I put the threshold also to 5 sats for the notification