Expand Pool button throws error

Currently running Scale 25.04.2.6.

In continuing to research why my vdev didn’t increase in size I found a couple of posts that pointed me to the Expand button on the Storage Dashboard. Except pressing it gives the following error:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/middlewared/job.py", line 515, in run
    await self.future
  File "/usr/lib/python3/dist-packages/middlewared/job.py", line 560, in __run_body
    rv = await self.method(*args)
         ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/schema/processor.py", line 174, in nf
    return await func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/schema/processor.py", line 48, in nf
    res = await f(*args, **kwargs)
          ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/plugins/pool_/expand.py", line 61, in expand
    await self.expand_partition(part_data)
  File "/usr/lib/python3/dist-packages/middlewared/plugins/pool_/expand.py", line 94, in expand_partition
    await self.middleware.run_in_thread(wipe_label)
  File "/usr/lib/python3/dist-packages/middlewared/main.py", line 627, in run_in_thread
    return await self.run_in_executor(io_thread_pool_executor, method, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/main.py", line 624, in run_in_executor
    return await loop.run_in_executor(pool, functools.partial(method, *args, **kwargs))
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.11/concurrent/futures/thread.py", line 58, in run
    result = self.fn(*self.args, **self.kwargs)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/middlewared/plugins/pool_/expand.py", line 91, in wipe_label
    f.seek(wipe_start)
OSError: [Errno 22] Invalid argument

Cheers.

I suggest that you file a bug report.

Possibly, iX did not consider the case of partial expansion on certain (special) vdevs when deciding that SCALE would no longer honor ZFS autoexpand property.