Funny thing about the Me410 timeline, and I didn't realize this until this past weekend when I did some reading...
The Me210 was produced and delivered for testing in early 1940. That's right, BEFORE the Battle of Britain!
There were the notorious instability problems of course (that stupid cranked wing was to blame for much of it), and it was found unsatisfactory. There were problems incorporating changes and delivering more units for more testing to the point where an official letter was sent saying there had been so many changes that any testing they were doing on the initial models was totally useless. They were very upset with Willi!
Now if he had just stuck with a straight wing leading edge, it wouldn't nearly have been so bad! Added his trademark leading edge slats like on the Bf110, and can you imagine a BoB flown with Me210s against Spit1s and Hurr1s? It would have been a slaughter! Alas, I suppose that's too much a what-if scenario but interesting to ponder!
410s were being produced in early '43, but I would say (my own $0.02) that you should really count them as a variant like the 109F is over the 109E. IMO the 410 had a bit of a longer lifespan than most folks think, if they consider the "teething problems" it encountered from 1940 onward.
Sorry for the tangent
