How long does it take to change from Fixed Pricing to Tiered Pricing and vice versa?

[timothylee]

In Interactive Brokers, when I go to the settings to change the pricing from Fixed to Tiered Pricing, does it take effect immediately? In other words, will my very next order or trade use Tiered Pricing instead of Fixed Pricing?

If after the first trade above, I immediately go to the settings to change the pricing from Tiered to Fixed, and place a new order, will that new order be using Fixed Pricing? If not, how long does it take for the change in pricing to take effect?

 

[NoahA]

I remember it being a whole business day. Certainly not instant, but still not bad. Since I did it after market close, it wasn't done yet the next day as it wasn't a whole business day in advance.