Man pages matching name shishi_kdcreq_postdated_p in section 3:

shishi_kdcreq_postdated_p.3.en	debian 10 / shishi-doc
shishi_kdcreq_postdated_p.3.en	debian 11 / shishi-doc
shishi_kdcreq_postdated_p.3.en	debian 12 / shishi-doc