My observations about AY81 "block" as AY Gold just after arrival to SIN:
1) Before T36 no block in EF
2) After T36 no block in EF, but OLCI showed seat next to me as occupied
3) Asked check-in staff at HEL if the seat next to me is blocked or occupied, she said that it's occupied
4) same question at the gate: gate agent replied that it's empty and will be kept so

= had all 3 seats in Y row 26 for us 2 (flying +1) on a flight where eco comfort was sold out. A comfortable day flight despite heavy delay (beer+wine ran out after 4-5 hours).