If I passed some basic exams before June 12-2024, are they valid for a Part 66 LMA license?

They are valid. The only difference is that the certificate of recognition on which they appear corresponds to the EASA 148 format, while the basic examinations approved as of 12 June 2024 will appear in an EASA 148a format if they have been carried out in a Part 147 organisation, or in an EASA 148b format (if they have been carried out with the Authority).