i think the main reason why the incubation period has a long range is because the virus is pretty new and not much is known about it. i believe that as time goes on and scientists know more about the virus they can shorten that range
Lol. You believe that this is a designer virus, eh?
I happen to agree and suspect that there are a selection of variants of coronavirus each with different 'gain of function' parameters all set up to go into production.
Since labs post job descriptions for people who have experience modifying bat coronaviruses, I think Occam's razor suggests that laboratories engage in modifying bat viruses.