You would not be notified if the seller removes the extra email notification setting from their account or products.
Frankly, if you believe the seller is so untrustworthy that they would try to cheat you out of your agreed-upon cut of sales revenue, perhaps it would be best to sign a written contract with them which would allow you to sue them for breach of contract if they do so, or simply not enter into partnership with them at all and sell your own books directly without their involvement.