I understand that there are reblooming lilacs, but the popular number of petals on lilacs is four, whereas on this shrub, four is the least popular number of petals. Leaves are opposite. Of course I don't remember if there was a fragrance.
The subtending smaller leaves don't seem right either - but otherwise it looks quite like a lilac. You might try a few garden centers to see if the same item is in stock.
Usually when lilacs bloom, it's April and I'm guessing it's not time for them to be putting out new branches, so there would not be those little leaves. Now that it's July, wouldn't those little leaves, if I'm understanding what you're both talking about, be how lilacs do their branching? I'm seeing a photo of flowers that look quite similar here, for Bloomerang (TM), which is Syringa x 'Penda'. http://www.calgaryplants.com/products/syringa-dw-bloomerang-lilac But this page compares 'Penda' with 'Josee' and says: "The tip of the corolla is weakly incurved for 'Penda' while it is strongly incurved for 'Josee'." http://www.inspection.gc.ca/english/plaveg/pbrpov/cropreport/lil/app00007394e.shtml I would have thought these corolla tips were strongly incurved. Of course, it could be something else entirely. The flowers are definitely fragrant. Here's another photo.
Sorry for all the fuss. This is actually at my building. I didn't realize it was new, and I didn't expect there still to be a tag. But the person who buys plants now keeps the tags, and says it's Syringa Bloomerang® Purple - Reblooming Lilac, from Proven Winners. He added that it keeps a few blooms going, rather than having distinct blooming periods.
I had looked at a photo of that or a similar selection earlier and noticed that it appeared to show a few flowers with 5 lobes.
