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Number of Unmatched Bets

This condition allows the automations rule's trigger to be filtered by the number of bets currently unmatched on a specified selection or in the whole market.
In this example the condition will only allow the rule to trigger if there are less than 3 unmatched bets in the market
Note: When using this condition to prevent a second bet from being placed until the first bet has matched you'd set the condition as 'the number of unmatched bets on the selection equals 0'.  However, the rearm rate on the General page needs to be set appropriately.  You need to take into account any betting delay being applied to the market (if in-play) and the frequency that the market is being refreshed. i.e. Having placed a bet, make sure the rule waits long enough before rearming to ensure the details of the bet (if unmatched) have returned from betfair.
Optimisation of the Bet Angel Guardian market refreshing can help... read more about it here.
Also, be careful using just this condition to filter betting when using global settings and offsets.  There will be a delay between the initial bet being filled and the offset bet being visible as an unmatched bet in the market (again based on in-play betting delays and Guardian refresh rates) there is a risk that the unmatched bets count for the selection will be tested as zero at this time.  To avoid an unwanted second bet, it is recommended that this condition be used in conjunction with the Fill or Kill Bet Time condition and that Fill or Kill is switched on in the global settings.