source files not updating

hello.
so, i have a resolve project with a bunch of jpg image sequences from c4d in a timeline.
each time i improve the work in c4d, i save over the jpgs [same file name: replaces the old version]
when i open resolve again, it works as expected, the new and improved version exists in the timeline where the old one existed before.
until...
i saved my final version at full resolution [1920x1080 instead of 960x540]. now when i reopen resolve, the changes are visually there...like: if i changed the colour of something in c4d before rendering out my final jpgs, that colour change is in the timeline; but: the resolution is still 960x540.
i can go one by one and replace each source file with itself and that updates to the correct resolution, but wow! is that tedious.
am i missing an obvious [or maybe a not-so-obvious] solution to this? why would resolve insist on importing 1920x1080 images at 960x540?
and, to be clear, the project resolution is, and has always been, 1920x1080.
thanks so much.

Check your Input Scaling maybe?

thanks jim.
image scaling is set at "scale entire image to fit"
it seems to me that if the source file is 1920x1080 and the project is 1920x1080,
then the files should import at 1920x1080.
i mean, when i originally imported the source file, it was 960x540
[because it was a low-res first draft render]
it seems like davinci is 'remembering' that size even when now the same source file in the same location is full-res.
this is maybe one of those 'no one else works this way' problems that davinci seems to deal out to me a lot. i do wish resolve were a bit more customisable... oh well.