Trouble with Greening and "Close Trade on Selection"

[showtrader]

Hi - I'm trying to green up my book close to the off in horse racing.

Rather than taking best price, I'm doing the following;

Green up all selections at best reverse price
After 3 seconds, cancel any bets which are not still at the best reverse price
Then "Close Trade on Selections with Greening" for any selections with no unmatched bets, at market price (i.e. the ones I just cancelled)
Then finally just green all at market with anything left over.

However, I'm finding that those selections which already greened up after the first trigger, are still getting triggered by the "Close Trade on Selection with Greening" trigger - even though they are already green.

Any idea why this might be?