A soft 15 is A,4 — an Ace counted as 11 plus 4. Here is the correct basic-strategy play against each dealer upcard (6-deck, S17, DAS).
| Dealer | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | A |
|---|---|---|---|---|---|---|---|---|---|---|
| Play | H | H | H | Dh | Dh | H | H | H | H | H |
S = stand · H = hit · D = double · Ds = double if allowed else stand
Against 4 the correct play moves once the count does. The other 9 hold across every true count you will see at a six-deck table.
The other 9 never move: against 2, 3, 5, 6, 7, 8, 9, 10 and an Ace the correct play at true count -3 is the same as at +7.
Break points come from the same count-dependent table that powers the strategy charts. The point gaps are computed by the engine for a full six-deck shoe.
See the row above for the correct play against each dealer upcard. It's for 6-deck, dealer stands on soft 17, DAS.
A soft hand contains an Ace counted as 11, so it can't bust on the next card. Soft 15 is A,4.
Yes, against 1 of the ten upcards. versus 4, hit becomes double at a true count of +1 or higher. The rest hold at every count you will see at a six-deck table.