Changing size in export doesn't change size
When exporting files via Save As, if I change the size, it doesn't update the actual export size until I do something else, like toggle the clip to artboard on and off or change from optimize for Art to for type. This has been a persistent error across versions of Illustrator and MacOS for some time.
Once you hit tab to leave that portion of the export dialogue, it should update without any additional steps.
Please get in touch with us at any of the other support channels – https://helpx.adobe.com/support.html . Since this is not a generic issue that we can reproduce at our end, we will need someone to look into your machine to figure out what is going on here.
Ashutosh Chaturvedi | Sr. Quality Engineering Manager – Illustrator