We know that Nazi Germany had stockpiles of first-ever nerve agents, sarin and tabun.

We also know that preventive civil defence measures that all countries introduced against WW1-era toxins would have been useless against nerve agents.

The decision-making process that led to Hitler deciding not to deploy nerve toxins is also well understood.

What I could not find is any kind of analysis of effects a decision to resort to using nerve toxins in the desperate late-war stage. For instance, if V-1s were used to deliver sarin and tabun instead of explosives to London. What would a single warhead with a tonne of nerve agents do? Would they disperse? Would they remain in one place?

We can assume a more concentrated initial campaign, as trying to achieve initial surprise makes more sense for nerve toxins than for high explosives. So, spring 1944, about 200 launches a day, 100 of which strike London each day for a week.