Thanks,
annonafox!
One thought is perhaps the site can limit/review the size (MB) of images/photographs - if this is a factor contributing to the space issues, that can be alleviated by managing/limiting those file sizes. The site could also, or alternatively, expunge photos that are older than x years, [or some other policy on how to treat old images.] That could also free up space and allow current users to continue posting images.
Your technical support might be able to advise if that can help.
JL