Maintaining Delta IV heavy means you need to maintain 3 of 4 Delta IV CBC production lines and two Delta IV launch pads on both coasts with an annual production rate of 3 CBCs and an annual launch rate of 1 for two pads, and you still call it cost-effective?
Yup. So I don't know that it really helps them much. But I think this part is interesting:
"We’re going to take [out] the redundant, more expensive Delta single-stick-line and fly only Atlas until we have NGLS available and until the government decides they’re done with [Delta 4] Heavy,” Bruno said"
Once FH is flying, the government may decide they are done with Delta 4H. Or at least, they'll agree to let ULA retire Delta IV entirely once there's a comparable LV available. The government won't let ULA do that until FH is flying and fully certified for DoD paylaods. D4H has only ever flown 8 times. And one of those was it's demostration flight and one was the Orion demo flight. So only 6 USAF/DoD payloads ever that needed it.
Looking here, it doesn't appear there are even any payloads manifested for it. And only a few more single stick Delta IV launches manifest through the end of the decaded. At least none that have been officially announced anyway.
http://en.wikipedia.org/wiki/List_of_Thor_and_Delta_launches_(2010%E2%80%932019)
So I wouldn't be surprised if this move will actually include D4H by 2018-2019, unless FH isn't flying and/or certified for DoD payloads by then. I believe ULA is probably, in an odd way, hoping FH gets certified so that USAF will let them full retire Delta IV and they can start using those assets to develop NGLV which I'll wager will use the D4 core tooling. That'll let them develop NGLV in parallel while continuing to operate Atlas, so they can do the switchover with little inturruption to manifest.
If there's an issue wtih FH certification, USAF will require ULA to maintain D4H readiness which would delay NGLV likely. Which is why they are only officially announcing the retirement of the D4M after if flies out it's current manifest. Once FH is certified in a year or two with USAF, they'll probably announce the retirement of D4H as well.
Then I think they'll restructure and streamline around the NGLV so as to be comepetative with SpaceX for both commercial and government paylaods and cut down to just one pad on east coast.
Be intersting to see if they would set up NGLV to launch from the Delta Pads so they could modfy them while Atlas continues to operate? And then retire the Atlas pads? Or if they'll modify the Atlas Pads for NGLV, and retire the Delta pads? That might be hard to allocate time for at LC-41, because unlike Delta IV, Atlas has a pretty busy manifest in 2016 and 2017 at LC-41, and I'd assume 2018 and 2019 and on would be similar. 9-10 launches per year makes it tough to shut down long enough to modify the pad. (SLC-3 would be much easier) They could build a 2nd VIF at LC-41 though, and then modify the Atlas VIF once NGLV is operating from the other and have two VIF's at there. Their current level of business, plus some additional commerical business that NGLV I think will be going after, could warrant two VIF's there anyway. I doubt a single facility will be able to launch NGLV at a faster rate than about once per month. 12 per year max with just one facility and ULA will likely expect to launch more than that with a single standard LV.
http://en.wikipedia.org/wiki/List_of_Atlas_launches_(2010%E2%80%9319)