Updating size of partially matched bet

[jptrader]

If you have placed a bet with a size of 100, half of the bet is matched, and you try to update the size to 75, what will happen? The size of the remaining part would increase (giving a remaining size of 75) or decrease giving a total size of 75 and a remaining size of 25?

[AlgoTrader]

If you have placed a bet with a size of 100, half of the bet is matched, and you try to update the size to 75, what will happen? The size of the remaining part would increase (giving a remaining size of 75) or decrease giving a total size of 75 and a remaining size of 25?

The BF API in the described situation is strange. If you place $100 bet, then adjust bet with originalSize = 1000 and newSize = 950 then $50 is dropped, $50 remained. Only the difference between origianal size and new size matters. That's weird, but that's it.