This is frustrating- we've been using Accept Hosted with DT Register since 2012 (when we contracted with Nathan to develop that payment gateway). To have it suddenly not be available with no warning and no contingency was a surprise, and really lets long-term customers like us down.
We've already been having issues with the latest updates, so we haven't been able to patch. Thank goodness, as we'll be remaining at this unpatched version until the Accept Hosted is re-implemented. Our clients must use that method on their websites to remain compliant.
In the future, please consider advising your customers before releasing a patch that removes something so critical for many clients.
Thank you.