There is no definitive answer to this question as it depends on the specific rules of blackjack that are being used. However, in general it is possible to switch cards in blackjack, provided that the proper procedures are followed.
In general, it is necessary to first check if the dealer has any blackjacks. If the dealer does not have a blackjack, then it is possible to switch cards. In order to do this, the player must place their original card face down on the table and then place the new card face up on top of it. The dealer then counts the number of cards that are showing and compares it to the number of blackjacks that are dealt.
If the new card equals or exceeds the number of blackjacks, then the switch has been successful and the player can continue playing with their new card. If not, then the switch has failed and the original card will be used again.
It is important to note that any rule changes that occur during a game (such as adding more blackjacks) will affect whether or not a successful switch can be made. So it is important to check with casino personnel before making any switches in order to be sure that they are allowed under the specific rules being used.
