Two questions:
1) What is the maximum file size that can be uploaded to DriveHQ via FTP?
If you have a very large file, it is strongly recommended using DriveHQ FileManager or FTP.
Using a web browser to upload a very large file or many files is not reliable and not efficient. Using DriveHQ FileManager, you can easily drag and drop many files / folders at one time.
DriveHQ FileManager supports any size files!! It is only limited by your available storage space. Moreover, FileManager can compress data for faster uploading (if your files can be compressed), it can automatically resume interrupted downloads / uploads.
You can also use any 3rd party FTP client software, most of GUI-based FTP client software can also support resuming. However, some FTP client software cannot support files larger than 2GB or 4GB. But DriveHQ FileManager can support files of any size. Note if you have such big files, it does take a very long time to upload / download.
2) How do I know what level of service I have?
I guess you mean which subscription plan? You can logon www.drivehq.com, go to My Account --> Subscribe --> Current Subscription.
Thanks for answering.