If a shard can't be loaded, should we start the other shards?

[mcpherrinm]

I'm not sure what the right answer here is, but while adding willow-2024h2c, the new config wasn't valid (wrong inception date, per #26), and so the existing shards also stopped running when Sunlight restarted with the new config, which isn't great. I'm not sure what the right course of action is, but I thought I'd note it as a pain point.