Update: Modern Warfare 3 Content Drops 4, 5 and 6 won't be released for premium Elite subscribers on PS3 on 12th April. Activision's Dan Amrich said the date was "a mistake", and the proper date is "TBD".
"I have been informed that this is a mistake and the date is still to be determined. I'll update you when I have a new, final date," wrote Amrich on his blog.
But Content Drop 3 - Overwatch - will still be released on 29th March. That wasn't a mistake.
Original story: Modern Warfare 3 Content Drops 4, 5 and 6 - map Black Box and Special Ops missions Black Ice and Negotiator - will be available to PS3 premium Elite subscribers on 12th April.
There or thereabouts, explained Activision's Dan Amrich - PSN dates are out of Activision's hand, and European localisation may alter the date very slightly. 12th April is a Thursday, which is an unusual time for PSN content to appear. The US usually updates on a Tuesday, and Europe on a Wednesday.
Before then, on 29th March, PS3 premium Elite subscribers will be able to download the Overwatch multiplayer map.
All of this Modern Warfare 3 content releases first on Xbox 360. On 20th March, Collection 1 - containing content drops 1-6 - will be released for Xbox 360. There's no date on Collection 1 for PS3.
There's a Call of Duty Elite content calendar for upcoming Modern Warfare 3 content. This changes dynamically according to the platform you select.