In reply to Sean Kelly:
Hiya, sorry for the late response.
Max photo size has changed from 250kB to 1MB.
Landscapes were resized to 1200px. They are now resized to 2540px wide, if they're above 1MB they are resized to 1920px wide, then again to 1200px if it's still too big.
Portraits were resized to 800px. They are now resized to 1440px tall, if they're above 1MB they are resized to 1080px tall, then again to 800px if it's still too big.
In a nutshell if you export at max 2540 wide and 1440 high and keep it under 1MB then the server won't have to do any processing and it should look the best it can. We will convert the JPG to WebP for display on browsers that support that format but that's it.
Post edited at 13:19