Use back or lay odds to determine favourites?

[shakespeare]

In every horse race there comes a point near the end when all the back prices disappear for the winning horse and there is only a lay price available at 1.01. For all the losing horses it's the other way round: all the lay prices disappear and there is a selection of high back prices available. This happens just before the market is suspended. I understand all that and it makes sense.

Yesterday I was trying out an automation that tries to place lots of small back bets on the favourite in the closing seconds of a race. The bot correctly placed back bets on the winner but it then carried on and also placed back bets on one of the losers. The only way I can see why this happened is that when the back prices disappeared on the winner, BA Professional used the remaining back prices on the losers to decide who was favourite. That's obviously not what anyone would want.

I see that there is a setting to force BA to use lay prices rather than back prices to determine the list of favourites. Do people use that option? Is it OK? Are there any gotchas I need to be aware of?

Thanks in advance!

[KenDoubleU]

You can probably use the following Automation Rule.
Add a Rule Type (under General tab) Fix Order of the Market Selection, at the time you make you first Back bet.

[shakespeare]

You can probably use the following Automation Rule.
Add a Rule Type (under General tab) Fix Order of the Market Selection, at the time you make you first Back bet.

Thanks. There's more than one way to fix the problem. I am setting a stop signal when any horse trades at 1.01. That stops any bets being placed on losers.

But I really wanted someone to help me understand the practical difference between using back and lay odds to determine the favourite. There must be some important difference, otherwise BA wouldn't have bothered giving us the choice.

[Dallas]

Its really just to give uses as much flexability as possible when creating their automation, Its no different to the options you have in some condtions like 'Fixed odds' conition where you can also ask the the to look at the back, lay or LTP of a selection.

Their is no right or wrong though personally i always use the back price with all mine but some may have automation where using the lay or last traded price to identify the fav works better.