CROCKD wrote:IdOp I checked and the new HISA trades as a mutual fund like a MMF ...
That's certainly true within limits, for example it has T+1 settlement like a MMF and the orders are placed through the Order Mutual Funds portion of WebBroker using a mutual-fund type symbol. However, the HISA is not a mutual fund and is not covered in the fund prospectus of the related-party fund family (e.g., TDAM and TD CT). For this reason I think it is not possible to switch. For example, if you had wanted to sell the monthly income fund (T+3) you'd have had to wait 2 days to buy the TD HISA (T+1).
In any case I checked to see if I could switch from the TDMI fund to the TD MMF (not HISA) and was told exactly as I have reported. It is because one half of the transaction involves selling a T+3 fund even though it is called a switch.
They really have to settle it at the brokerage account in T+1, otherwise your account could be in deficit for 2 days (as adrian2 pointed out earlier). Now, that said, for tax purposes what matters is what the broker reports to CRA, and this is summarized on the annual T5008 form ("Trading Summary") that we get each new year. When I get a chance I will try to find an old example of this and see if the settlement date on the T5008 matches what was reported for the switch. I realize this will probably be too late to help you, but my curiosity about this is now at the point where I need to know.

In any case it is no big deal. I was trying to do some year end tax planning - should not have left it so late. But it can wait till next year.
It's good to know this wasn't highly critical.
It occurs to me that if you sell stock or mutual funds because in an emergency you need cash, you would have to wait three days for it ...
In the case of a mutual fund, you can get it in 2 days, by switching to the MMF in the same family, then calling the broker the next day to sell the MMF. I have done this at TD-W, and it worked, though there could be a small risk if the reporting stream of the first trade got fouled up. But if you need money in a pinch (say to cover a late-day stock purchase) it can be worth knowing about this.