Is 以降 inclusive? If I say: > 16[]{} It means I cannot participate after the 16th. However, what about on the 16th? Is it also implied that I cannot participate on the 16th either? Or, that I can participate on the 16th, but not after?

Yes, it is inclusive. All the similar phrases that use are inclusive: . However, unfortunately a lot of people do not know this and use them carelessly without thinking.

If you wanted to express "After the 16th but not including it", you could say:

> 16

However, I would be more inclined to say:

> 17