According to OLG
"For most sports, under PROLINE+ Game Conditions whenever an event offered for sports betting is postponed or cancelled, the odds for that selection on a bet reverts to 1.00 and the selection will be deemed “Void". However, if there has been a conclusive result in a Market at the time of abandonment, all bets on that Market will stand"
CANCELLED/ POSTPONED EVENTS | Proline Support
"For most sports, under PROLINE+ Game Conditions whenever an event offered for sports betting is postponed or cancelled, the odds for that selection on a bet reverts to 1.00 and the selection will be deemed “Void". However, if there has been a conclusive result in a Market at the time of abandonment, all bets on that Market will stand"
CANCELLED/ POSTPONED EVENTS | Proline Support