Cloud Sync (rclone) bandwidth limit

For a Cloud Sync task, I’m trying to set the bandwidth limit such that it stops uploading at 17:00 until 00:00 (peak hours according to my ISP).
Truenas complains however about the limit being smaller than 1 when trying to save the task.

The limits I’m trying to set are: 00:00,off 17:00,0

This should be a valid parameter, according to the rclone documentation.

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/middlewared/main.py", line 211, in call_method
    result = await self.middleware.call_with_audit(message['method'], serviceobj, methodobj, params, self)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/main.py", line 1529, in call_with_audit
    result = await self._call(method, serviceobj, methodobj, params, app=app,
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/main.py", line 1460, in _call
    return await methodobj(*prepared_call.args)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/service/sharing_service.py", line 148, in update
    rv = await super().update(app, audit_callback, id_, data)
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/service/crud_service.py", line 240, in update
    return await self.middleware._call(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/main.py", line 1460, in _call
    return await methodobj(*prepared_call.args)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/service/crud_service.py", line 261, in nf
    rv = await func(*args, **kwargs)
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/schema/processor.py", line 49, in nf
    res = await f(*args, **kwargs)
          ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/schema/processor.py", line 178, in nf
    args, kwargs = clean_and_validate_args(args, kwargs)
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/schema/processor.py", line 172, in clean_and_validate_args
    verrors.check()
  File "/usr/lib/python3/dist-packages/middlewared/service_exception.py", line 72, in check
    raise self
middlewared.service_exception.ValidationErrors: [EINVAL] cloud_sync_update.bwlimit.2.cloud_sync_bwlimit.bandwidth: Should be greater than or equal to 1

I’ve now set it to “17:00,1”, which is 1 B/s so very slow anyway, but is this a bug?