I think that's too long for OCI #2. Chevys load up the oil with Tons of junk at break in. I would do 3K, maybe. Depends on how it looks and feels and smells.
So you're at 1500, just changed, and sounds like you are planning to go 7k on dino now. Cool...so with 5500 raining I'd take the current fill 2500 and the following fill 3000.