Just wrapping up my brew day (10 gallons of RIS) and I realized two things.
Firstly, I was not happy with my OG thinking it was too low. Then I realized that I only added DME for a 5 gallon batch, so my mash efficiency has actually increased significantly since the last brew. Nice. Glad for that.
Then I realized, I had only added hops for a 5 gallon batch. Not so nice.
I know this is a tough one to fix and I probably need to re-brew and blend.
I have extra wort in the freezer and could probably boil that with the missing hops and add it the to fermenters. Not sure if that's a good idea or not. I probably have 1 gallon or so.
The lesson for the day is, adjust the recipe in advance for 10 gallons rather than trying to work it out on brew day.