If the scheduled duration of a match is reduced or increased in the number of games/sets required to win, all bets will be void except for those on markets that have been unconditionally determined. Please note that this does not apply to Match Odds or Set Winner markets on Davis Cup matches or ‘dead rubber’ matches that have been shortened from five sets to three sets after the market has been loaded, provided that the match has been shortened in accordance with the competition’s rules.
Bets will stand regardless of changes to scheduled venues, including any changes to a different type of surface.
Bets relating to the number of occurrences of certain events within a tournament will be void if the tournament is reduced in length, postponed or cancelled, except for those on markets that have been unconditionally determined.
If a player or pairing retires or is disqualified in any match, the player or pairing progressing to the next round (or winning the tournament in the case of a final) will be deemed the winner. All bets relating to individual games or sets within a match will be void, except for those on markets that have been unconditionally determined. If less than one set has been completed at the time of the retirement or disqualification, then all bets relating to that individual match will be void.
The Exchange General Rules and Market Information will apply in respect of any category of bets or markets not referred to in the Specific Sports Rules. If there is any inconsistency between the Specific Sports Rules and the Exchange General Rules, the Specific Sports Rules shall prevail. If there is any inconsistency between the Market Information and either the Exchange General Rules or the Specific Sports Rules, the Market Information shall prevail.
See here for the Exchange General Rules.