The Stack Exchange API documentation is ever so slightly confusing wherever Unix timestamps are mentioned (perhaps any ranges, I haven't dug too deeply)
todate – Unix timestamp of the maximum creation date on a returned item.
unix epoch date, range [0, 253,402,300,799]
It took me a very brief moment to understand what was intended by the italicized part. For clarity, perhaps this should be edited to one of the following:
...unix epoch date, range [0, 253402300799]
...unix epoch date, range [0 .. 253,402,300,799]
...unix epoch date, range [0 - 253,402,300,799]