Whose limit order is sent out first?

If 3 subscribers are on auto-trade for a strategy X - in what sequence are the limit orders sent out? Random? Or the order in which the subscribers enabled auto trade for strategy X?

I think this is an important question and I am surprised it has not been answered yet.

Thanks for bumping the thread. This is something that only Matt Klein etc can answer.

The sequence of orders going out is randomized.