No market orders allowed for tradings outside regular trading hours. In fact, if you had a market order set to execute during the market hour, if the execution time is set too late, it won't even execute as soon as IB decides it's outside of regular trading hours. Had that happen to me once, so annoying. I ended up losing a super good entry opportunity.
Marketable limit order will work, just not a market order. Market orders are like writing a blank cheque. Atleast with a marketable limit order you can set some boundaries to protect yourself from vanishing liquidity.