The substitutions didn't work, that's football. What changes would have made then?
Jone has been effective coming off the bench most of the time, it was only last week his shot led to the goal. If you're saying you wouldn't bring him on, you're being reactionary. Bayliss is our most attacking CM, if you want to win a game, you'd bring him on over more defensively minded midfielders, as previously mentioned, Walsall had started to stand off us. We've established you'd have brought on Bakayoko, who apparently had a shocker for the U23s and is not actually a target man - a lot of people probably wanted to see him score v Walsall, myself included, but Chaplin is the better striker.
Perhaps we should've subbed Jones on for Shipley, and moved Hiwula in the middle for a 4-4-2. This said, Hiwula was playing well down the left (better than Thomas this week) and so far Hiwula has had most of his success on that left wing. Shipley also looked quite likely to score in the first half too and does have a knack of being involved in goals.
Your take on the game is limited, you've only observed what didn't work, without any consideration for why the subs were made. We tried to the win the game and we didn't. It was a low stakes game and it's fairly obvious had it been a league game we would've been conservative and took and point. The only prize for a draw yesterday was a replay no one wanted.
The bottom line is, the substitutions didn't pay off, but you're being overly critical if you don't think they were logical.