I found a festival called Offering Sacrifice to Nebet Het and Wesir on 13 of Boedromion (mid-September) which is why on the Egyptian calendar I put it on 2nd Akhet Day 13.
On this festival They were offered milk and water mixed with honey, fruit and a cockerel.
As is Greek custom for purifying sacred space, wheat and barley were scattered.
Here is the source: Alvar, Jaime. Romanising Oriental Gods: Myth, Salvation and Ethics in the Cults of Cybele, Isis and Mithras. (Brill Academic Pub, 2008), 313-314.
Fiercely Bright One 
Does it give a reason for what the festival is for? I find that an interesting combination (not that it’s implausible)!
It is just listed in a festival calendar: “Hadrianic sacrificial calendar”. I’m not seeing a reason mentioned besides making offerings to Gods. We’re really lucky to have the offerings listed with it. I don’t have much more information besides that.
Ahhhhh, this is fantastic to know about! They’ve both been a huge help to me in a matter of complicated grief, will definitely be looking in to this one. Thank you!
My condolences. You’re welcome.