Yeah there is a severe shortage of iPhone 7 plus. Here in Qatar the carriers started pre orders (Ooredoo and Vodafone ) had the iPhone 7 plus in all modes sold out in like the first 10 minutes after midnight. But all model availablity with the regular 7.
Seems like Apple underestimated how many people wanted the plus this time around. I think the dual camera is attracting lots of folks to the plus.