I think it depends on how much solids are consumed and how thick the mixture is. When we started on cereal it was quite runny so I didn't offer water or a bf snack. At closer to 8 mths I was making her food thicker and she refused water so I sometimes offered her a bf drink from one side, she would take a few drinks only for a minute or two. I continued to offer water first directly after her solids, it has only been recently (around 10 mths) that she actually will drink some water so I stopped the bf drink. Now that she's older I also don't wait an hour anymore, I bf her and then give her the solids right after, then some water. I wouldn't bother with the syringe of water, he can't be that thirsty otherwise he'd take some on his own. If you're using a sippy you may find that by taking the stopper out the water will drip out and he'll take it if he's thirsty.