When you close a short, the correct Date Acquired is the date you closed the trade.
For options, Date Disposed is one business day later. Stock settles in two business days.
If you have a profit, Date Disposed is the same as Date Acquired.
Some brokers report this correctly, some do not.
As far as dates go, TD Ameritrade is one of the brokers that supplies a correct 1099-B in compliance with the IRS reporting rules in the IRS Publications.
