Yep, it was a clog. Mud-dauber wasps had filled up the central burner passage with their nests, eggs and larvae. A friend at work helped me get the rusted bolt holding the central ring that looks like a cogwheel. Some penetrating spray and rubber mallet whacking later, it all came apart. Then after some bottle-brush time and lots of Eeeww later, the burner was finally clean inside and out.
Made pizza for a Supermoon party across the street. Small party, 4 adults and 2 kids... only made 4 pizzas, no pics. A shame because the host went out and bought really great toppings: all the toppings needed to make the classics. Margherita, L'Atomica, Bianco, etc. It was good to get back into slinging pies after a long interruption.
Got reminded of a few pertinent factors: 1. humidity adversely affects dough opening, so choose a lightly fermented low-hydration recipe if expecting moist environmental conditions. 2. Conductivity of almost any stone you can put into an LBE is going to be higher by a factor of .33 than the firebrick in a wood-fired masonry oven, so adjust your cooking temperature to 2/3 of "ideal" WFO. For my stone, a top surface (average) stone temp of 550 is perfect. Any more than that, I'd better be using Caputo.
Pizzas made that night were: all-cheese for the kids (@550): very nice! Pepperoni, portabellas and hot peppers @ 650 (charred, but tasted good) Sicilian in a cast iron skillet @ 525 for 6 minutes: ham + pepperoni, shiitakes, fontina & mozz, drizzled olive oil (belly-bustin addictively tasty) and then made a last Sicilian with just cheese and garlic to leave for next-day leftovers.