For all futures & options contracts, there is a range in which the orders can be placed, orders can’t be placed above or below the price of this range. If you open the market depth/snap quote(F5) window, you will be able to see this range.
If you open market depth window,
There are two items in it which shows the range of prices you can enter in your AMO or any order.
Lower Circuit Limit
Upper Circuit Limit
Set your AMO Limit order price between these two values, otherwise your AMO will be rejected.
To open Market Depth window in Z5, right click the stock option from your Market Watch and choose Market Depth in the pop up menu.
Usually for stock options, the upper limit is much more than 100%, in fact it will be in multiple times. So yes you can set a sqaure off order more than 50 to 100% on current premium price. You should find a counter party willing to take your square off, That would be the difficult task.