Received a Federal Benefits Credit for deceased parents

My parents both died last February. I reported it to the SSA and their monthly payments, which were direct deposited to their checking accounts (one in solely my mom's name at Fidelity and my dad's went to their joint account at US Bank), ceased. My dad's monthly payment was about $1200 and I don't know what my mom's was.

Today I woke up to a notification of a Federal Benefits Credit of $2700 deposited to the US Bank account. However, that account is solely in my name now as I was on it as beneficiary. I don't know if a similar deposit went to my mom's Fidelity account - I was never on it and it was closed and the money transferred into my personal account there via small succession affidavit.

I will call the SSA on Monday, but I'm wondering if anyone knows if this is a flub on their parts or if there is some sort of benefit given to survivors that I'm unaware of.

I'm 53, so not eligible for child's benefits, and they were a uniform simultaneous death so I don't think there's any surviving spouse benefits. I'm also concerned because it's my name on the account now but it was deposited there anyway. This account is in a separate bank from my personal account so no chance it was meant for me.