CVS Online Order – Extra Bucks & Canceled Item Questions

Hey everyone, I placed an online order at CVS to buy 3 Crest items and qualify for the $5 Extra Care Bucks (ECB) deal. However, the store only had 2 in stock and canceled the third item.

1.  Will I still get the $5 ECB even though only 2 items were fulfilled?

2.  If I return the 2 Crest items, what happens to the ECB I originally rolled into the purchase? Will I get them back, especially if I used more ECB than my final order total?

Has anyone experienced this? Thanks for any insight!