Thanks. That's good to know.
There seem to be other problems with Plan Image.
Sometimes when I change the plan image, the change is reflected in the display of the field, and sometimes it isn't. The database table is updated correctly, but the old image displays anyway. (No, it's not a cache problem. The files are named differently and I've cleared the server and browser caches.)
Also, sometimes when copying a plan, the plan image will not display. The database record is correct but the spot where the img tag should be is empty in the html output.
I should mention that all these plans are children of other plans. There is no plan image for the parent. I wonder if that could be affecting things?
I have a large number of plans to manage so workarounds for each of them is going to be a problem. Fortunately, the plan images aren't a show-stopper.
Thanks for listening and for the quick responses.