Make sure to watch the # of diapers in the box when doing subscribe and save. I just discovered that for pampers baby dry size 5 the box size went from 172 -> 156.
I thought I had to create a new sub to apply a coupon, so it showed me 156. But that was higher priced per diaper than the 172 count. I still have 172 in my subscriptions, so I was able to get that instead (and it applied the coupon), but you can't create a new sub with 172. It looks like the 116 count is S&S eligible and actually the same per diaper as the 172, but 156 is higher.
(and if you keep refreshing your coupons you can get other ones to appear, pampers wasn't there initially, but after a few F5s it appeared.)
Re: psa: amazon S&S diapers - watch box size