Automatic dividend deposit is currently broken, at least for Vanguard ETF and funds: frequent problems are dividends applied to accumulating funds, wrong currency (GBP instead of GBPx pence or viceversa), sometimes flat out incorrect dividends.
I would like to keep using the "Buy and sell with available cash" feature of cash management but currently I have to manually add fictitious cash transactions to compensate for wrong dividend deposits.
I'm conscious that dividend errors might be due to incorrect source data which Yahoo cannot correct, that's why making "Deposit dividend payments into your cash" and "Buy and sell with available cash" individually selectable might be the best solution.