SQL Server 2019

By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.

CREATE TABLE A (
    [date]     DATE,
    [time]     TIME
);
INSERT INTO A VALUES
('2021-12-24', 	 '9:30:00'),
('2021-12-24', 	'10:00:00'),
('2021-12-24', 	'10:30:00'),
('2021-12-24', 	'11:00:00'),
('2021-12-24', 	'11:30:00'),
('2021-12-24', 	'11:00:00'),
('2021-12-24', 	'11:30:00');

CREATE TABLE B (
    [date]     DATE,
    [time]     TIME
);
INSERT INTO B VALUES
('2021-12-24', 	 '9:30:00'),
('2021-12-24', 	'11:00:00'),
('2021-12-24', 	'11:00:00'),
('2021-12-24', 	'11:30:00');



11 rows affected

SELECT * FROM A


date
time


2021-12-24
09:30:00.0000000

2021-12-24
10:00:00.0000000

2021-12-24
10:30:00.0000000

2021-12-24
11:00:00.0000000

2021-12-24
11:30:00.0000000

2021-12-24
11:00:00.0000000

2021-12-24
11:30:00.0000000


WITH cteA AS (
    SELECT *, ROW_NUMBER() OVER(PARTITION BY [date], [time] ORDER BY [time]) AS rn
    FROM A
), cteB AS (
    SELECT *, ROW_NUMBER() OVER(PARTITION BY [date], [time] ORDER BY [time]) AS rn
    FROM B
)
DELETE cteA
FROM       cteA
INNER JOIN cteB
        ON cteA.[date] = cteB.[date]
       AND cteA.[time] = cteB.[time]
       AND cteA.rn     = cteB.rn;
4 rows affected

SELECT * FROM A;


date
time


2021-12-24
10:00:00.0000000

2021-12-24
10:30:00.0000000

2021-12-24
11:30:00.0000000

date	time
2021-12-24	09:30:00.0000000
2021-12-24	10:00:00.0000000
2021-12-24	10:30:00.0000000
2021-12-24	11:00:00.0000000
2021-12-24	11:30:00.0000000
2021-12-24	11:00:00.0000000
2021-12-24	11:30:00.0000000