Here's a piece of good news. Knowing how molecular process work, I figured protection from the day of vaccination is likely not linear, but more exponential; that is, you get the biggest bang for the buck in the early days.
I've been looking for the actual data, and happened to see briefly on TV one graph that showed 80% effectiveness just 9 days after the 1st shot, but I have been unable to find the source of that graph. Now, I clearly heard a doctor being interviewed on TV about the delays due to weather and how that might affect folks getting their 2nd shot. The statistic quoted was that you are already 85% protected on the day your 2nd shot is scheduled just from the 1st shot. So that's comforting.
P.S. What is unknown is whether the 2nd shot allows the protection to last far longer. That may well be, but it may also be that the 2nd shot is not all that important. It is possible that in a time of vaccine supply shortage a good strategy, which some countries are already using, is to delay 2nd shots in order to vaccinate more folks with at least one shot. Best, of course, is to stick with the tested protocol, but when push comes to shove.......