Yes, in ldap filter of the LDAP OU Definition, you never have (&(objectClass=user)(sn=*)(!(objectClass=computer))(whenCreated>=#DATE#)(extensionAttribute4=*))

First time you put manually a real LDAP filter like this : 

(&(objectClass=user)(sn=*)(!(objectClass=computer))(whenCreated>=20210304000001.0Z)(extensionAttribute4=*))

Then in post script, script translate to next filter

(&(objectClass=user)(sn=*)(!(objectClass=computer))(whenCreated>=#DATE#)(extensionAttribute4=*))

to

(&(objectClass=user)(sn=*)(!(objectClass=computer))(whenCreated>=20210311000001.0Z)(extensionAttribute4=*)) 

and update LDAP OU definition filter with this new dynamic filter.

Best regards