I grabbed this screen grab that looks like they might have added to the T/E as as shoulders for the F-H launches. (This is from the SES launch campaign).
Though I found a shot of the base of the T/E in the hangar, and there is not yet 'room' for two more cores on the blast pad at the base.
Actually that is a Dragon on the top (You can see the solar panels) so that is a much earlier launch and in fact, the shoulders you can see above in the picture are missing. So a useful picture still.
F-9 CRS-3 mission photo, focusing on the landing legs, shows the lower shoulders really clearly.
As you look at the base, you can also see the wider base. So looks like much work has been done.
From the Jun 20, 2014 ORb2 launch attempt, SpaceX published a couple of shots, where you can see the T/E, and it looks a bit different again.
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