Amazon subscribe and save is THE biggest scam.
Big price fluctuations mean you're almost certainly paying way more than your 10% saving next time the order rolls around, and you don't even get notified when the order happens!

@bbrks I get an email every month letting me know it is time to review the order, and the review page shows any price changes. It's the one service that I find useful from Amazon shopping.

@kevin Maybe there's something funky with my notification settings or Amazon UK! Thanks, I'll go and check.
The scheduled deliveries are an excellent forcing function for me to do things (e.g. give my dog worming tablets)