Now possible to come to Brest and big area around it visafree for 10 days. However, need to contact a BY tour company to get you registered, arrange your travel plan and book accomodation for you (if you come for more than one day).
You can come to Brest by train (Warsaw-Brest, for example), by car via Terespol-Brest, Polowce-Peschatka or Slawatycze-Domachevo crossing and by plane.
Official Brest visafree website with tour company contact info still not available. More details will follow.