PM is a rebloomer so, in addition to the early Spring flush, it tends to open new flower buds in the summer/fall. Those that you see now are the Summer/Fall Flush. I have a Pistachio that is a rebloomer too and it is fixing to go into the broccoli stage in 1-2 weeks now that the 90s are starting to become history here.

I do not think it was the house position. Last year, all of my mopheads' flower buds were zapped by bad weather in January 6-9 after several weeks of mild winter that broke dormancy.

We got to the mid teens down here and you probably got to the single digits. That probably killed the flower buds that would have normally opened in Spring 2017. You got a few ;o) but I got no blooms :o( from my mopheads. Consider using winter protection this year or at least consider applying winter protection if you see really cold temps approaching. It should give you more reliable bloomage. This year, weather.com warned of the chance for a La Nina Event so expect whatever kind of weather that it brings for KY (cooler/warmer/normal temps or drier/wetter/normal precipitation). Note how even in my Z8, I sometimes need protection!

I typically use chicken wire and throw in mulch. You can stalk burlap around the bushes and fill with leaves too. Just make sure you protect the ends of the stems, which is where the invisible flower buds reside for Spring 2018. And use a lot of leaves. I try to have several inches between the ends of stems and the chicken wire (3-6", it varies).

It is ok for frost to finally zap your blooms at some point if they are not brown yet. It also does a number on some leaves that leaves them looking a yucky dark green to blackish color. I sometimes wait for a late frost and, weeks afterwards, I will then put my winter protection around the shrubs. Waiting a few weeks after the late frost lets the leaves brown out and I can "see" inside the bush to see if there are weird or crossing branches that I may want to prune. It is so hard to see when they are leafed out, isn't it? ;o)

My LAD is looking the same: buds that look like they could even bloom this fall rather than patiently waiting for spring. Mine are also right next to my home (though I'm a bit north) and I've gone back and forth about wrapping in burlap - I wasn't planning on it, but I'd be sad if I missed out on spring flowers. My neighborhood is filled with hydrangeas that people don't wrap, so I'm hoping that mine also turn out ok.

LAD is supposed to be a rebloomer too but in your zone, I would have expected to see flower buds closer to the Summer. Hope that what you are seeing are leaf buds and not flower buds. And hope it is just a few. When the buds are small, you can't tell leaf and flower buds apart. One word of caution regarding winter protecting:

Be careful with that this year. We may get a La Nina Winter per weather.com so just keep an eye tuned to the weather. Especially if you do not winter protect.

Depending on one's location, it may result in unusual weather changes that might affect hydrangeas. I did not winter protect last year and even with my mild weather, I got zapped. Example of issues you can expect with a La Nina Winter and which vary depending on your location: it may be drier than normal (so keep an eye on soil moisture and water if dry indeed and if the soil has not frozen); it may be wetter than normal (so save money and turn off the drip and sprinklers); it may be colder than normal (so winter protect); it may be warmer than normal (so winter protect too). This last one sounds odd but it got me last year. Winter was mild to start and did not get going until early January, when temps just crashed in to the teens. The mopheads that bloom on old wood never went fully dormant with daytime temps in the 50-70s and their flower buds or their stems got zapped and prodcuded almost no blooms in Spring.

The important thing to keep in mind is that when they predict long term, they may say things like it will be warmer than normal (for example). But there will still be times when you may get "normal" weather or even the opposite of what was forecast. Last winter was El Nino, they advertised mild temps for me and that was true for a month. I got used tothat, dropped my guard, stopped paying attention to the weather forecasts and got caught unprepared when temps crashed to the teens in January. Jeeez, it was not until after the cold had hit that my brain woke up and asked if the hydrangeas had been winter protected. Oops. I even had the materials beside the bushes to be used at any moment but, ooops! Hee hee hee. (insert a big ooops smile here).

Of course, if you typically get dead stems after every winter, you could gamble and leave them unprotected. But ck the long term forecasts if you can. It is supposed to be drier and warmer than normal for me. Since the warmer part got me last winter, I will selectively apply winter protection to those that got zapped last winter first. Now, I have time to do all that since they usually go dormant late Nov or in Dec.

Yeah, I'm pretty sure it is a flower - at first I thought it was leaves until it started to open up.

Hee hee hee. I know that surprised look. Got it myself in early October when Blue Deckle put one bloom out on each of two of those plants that I have. Normally, Fall triggers this effect but on a limited number of blooms. And not on all mopheads. I have a mystery hydrangea that does the same thing about once every 3-5 years. The other mopheads have not done that before.