What colour is dad and the grandparents? If they aren't grey then you stand a good chance if having a solid bay there. Bay is a dominant colour anyway, but grey is always the "mask". Judging from his colour now and his mum, you say his sire has a blaze so I'm assuming he isn't a grey, then he won't grey out.
He's a cracker, I really like him!
He's a cracker, I really like him!