Last year, the first tape dates were up by May 10th so this delay is out of the ordinary.
Here's a list of when they taped the first show of each of the past few seasons:
Season 45 - July 18
Season 44 - July 6
Season 43 - July 21
Season 42 - June 24
Not too much there to go off of, but if you could plan for July 24th to be safe it looks like that should work.