This policy has been in place since at least 2016.
For any recreational Club which plays in any cricket competition, league or match which is governed by the ECB, the eligibility of a trans person is determined as follows:
11.1 any trans person may compete in any mixed gender competition, league or match in their affirmed gender or preferred gender identity and should be accepted as the gender they present or in their preferred gender identity;
11.2 a transgender man may compete in any open competition, league or match and should be accepted in the gender in which they present, but may not compete in any female only competition, league or match;
11.3 a transgender woman may compete in any open competition, league or match or any female only competition, league or match and should be accepted in the gender in which they present; and
11.4 an individual identifying themselves as non-binary may compete in any open competition, league or match and should be accepted by reference to the gender identity in which they present but may not compete in any female only competition, league or match.
So males may play in any game, but some females may not play in women's games.
This is how the ECB ensures its commitment to
...the principles of diversity and inclusion in cricket.
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- The ECB aims to ensure that all people, irrespective of their:
3.1 age;
3.2 disability;
3.3 gender identity;
3.4 marriage or civil partnership status;
3.5 maternity, pregnancy or breastfeeding status;
3.6 race (including ethnic origin, nationality and colour);
3.7 religion or beliefs; or
3.8 sex, social status or sexual orientation;^
^
have a genuine and equal opportunity to participate in cricket in England and Wales at all levels and in all roles and that they are treated fairly, equally and with respect.^
https://platform-static-files.s3.amazonaws.com/ecb/document/2019/04/26/3bb659af-9a7d-4ffa-810d-7fae32959ee6/Non-First-Class-ECB-Regulations-Transgender-2019.pdf