Upload to Google Drive
If you enabled the "Use Wifi Only" option in Boldbeast Recorder, the app checks the Wifi state upon uploading a file, if Wifi is disconnected it doesn't upload the file otherwise it uploads the file. For example the file is 80 MB, you'll see the app displays "Upload completed!" within 2 seconds. Why is it so fast? Because the file is not really uploaded, actually the file is received and cached in the phone by Google Play Services, later Google Play Services upload the file itself.
Which one does Google Play Services use to upload, Wifi or your 3G/4G data plan? This is out of the control of Boldbeast Recorder, you should properly set the Google Play Services. So if you want to use Wifi Only, please set like this: Open the "Google Settings" app, click "Data management > Update Drive-enabled app files", change it to "Over Wi-Fi only".
Upload to Dropbox
If you enabled the "Use Wifi Only" option in Boldbeast Recorder, the app checks the Wifi state upon uploading a file, if Wifi is disconnected it doesn't upload the file otherwise it upload the file. During uploading if Wifi changes from connected to disconnected the app stops uploading. Later when Wifi is connected again the app resume uploading.