MySQL 8.0

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CREATE TABLE tbl_crps(id         integer,
                      crp        integer,
                      starts_on  date) AS
SELECT 1 as id ,  20 as crp , "2020-02-09" AS starts_on UNION ALL
SELECT 2 as id ,  31 as crp , "2019-06-05" AS starts_on UNION ALL
SELECT 3 as id ,  20 as crp , "2018-01-10" AS starts_on UNION ALL
SELECT 4 as id ,  31 as crp , "2021-07-03" AS starts_on UNION ALL
SELECT 5 as id ,  58 as crp , "2022-01-01" AS starts_on UNION ALL
SELECT 6 as id ,  58 as crp , "2025-02-02" AS starts_on;
SELECT *
  FROM tbl_crps
  ORDER BY id


id
crp
starts_on


1
20
2020-02-09

2
31
2019-06-05

3
20
2018-01-10

4
31
2021-07-03

5
58
2022-01-01

6
58
2025-02-02


WITH cteData AS (SELECT b.CRP, MAX(b.ID) AS ID
                   FROM tbl_crps b
                   WHERE b.starts_on <= "2020-10-02"
                   GROUP BY b.CRP)
SELECT *
  FROM tbl_crps a
  WHERE a.ID IN (SELECT ID
                   FROM (SELECT b.CRP, b.ID
                           FROM cteData b
                         UNION
                         SELECT d.CRP, d.ID
                           FROM tbl_crps d
                           WHERE d.starts_on > "2020-10-02" AND
                                 d.CRP NOT IN (SELECT crp
                                                 FROM cteData)) c)


id
crp
starts_on


2
31
2019-06-05

3
20
2018-01-10

5
58
2022-01-01

6
58
2025-02-02

id	crp	starts_on
1	20	2020-02-09
2	31	2019-06-05
3	20	2018-01-10
4	31	2021-07-03
5	58	2022-01-01
6	58	2025-02-02