I think our game/squad has evolved to need to rely less on our Billy than before.
Yes, of course he's a top finisher and would love him to be fit and available, but we seem to be developing into a team of all rounders with enough skill to be able to create chances for anyone from anywhere.
We almost don't need an out and out old fashioned centre forward, and for when we do, we have Brewster+ for the finishing, McB for if we need to go more direct.
Billy's record speaks for itself, and with any other set up I'd be far more worried if we didn't have the creativity and 'goals from anywhere' potential we have now, but still want him in and around in any capacity, the true professional and superb advocate for our club that he is.