Have an old DOS based bj simulator, what does "Q" mean?

[binki]

I have an old (1985) bj simulator that I used to use a lot. I took a look at it the other day and the strategy section has S/H/D/Q for Stand/Hit/Double/? For the life of me I cannot remember what Q is for.

The supplied strategy shows a Q if the player holds 16 and the dealer shows 9/10/A, player holds 15 and the dealer shows 10/A, player shows 12/13 and the dealer shows A.

Any ideas on what this is?

TIA