ZEC stopped syncing after HF activation

[cipig]

NU6.3 (Ironwood) https://zips.z.cash/zip-0258 was activated on block 3428143 and electrumx stopped syncing
the error shown is this:

INFO:DB:height: 3,428,142
INFO:DB:tip: 00000000008b2ffd813f6a09372b4c9da20caad248245086445c19770ac270dd
INFO:DB:tx count: 17,919,259
INFO:DB:flushing DB cache at 1,200 MB
INFO:History:history DB version: 1
INFO:History:flush count: 250
INFO:DB:deleted 116 stale undo entries
INFO:SessionManager:RPC server listening on localhost:8058
INFO:Prefetcher:catching up to daemon height 3,428,214 (72 blocks behind)
INFO:Prefetcher:cancelled; prefetcher stopping
INFO:SessionManager:closing down server for rpc://localhost:8058
INFO:Controller:shutting down
INFO:Controller:shutdown complete
ERROR:electrumx:ElectrumX server terminated abnormally
Traceback (most recent call last):
  File "/usr/local/lib/python3.13/dist-packages/electrumx/cli/electrumx_server.py", line 35, in main
    asyncio.run(controller.run())
    ~~~~~~~~~~~^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.13/asyncio/runners.py", line 195, in run
    return runner.run(main)
           ~~~~~~~~~~^^^^^^
  File "/usr/lib/python3.13/asyncio/runners.py", line 118, in run
    return self._loop.run_until_complete(task)
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^
  File "uvloop/loop.pyx", line 1518, in uvloop.loop.Loop.run_until_complete
  File "/usr/local/lib/python3.13/dist-packages/electrumx/lib/server_base.py", line 129, in run
    await server_task
  File "/usr/local/lib/python3.13/dist-packages/electrumx/lib/server_base.py", line 102, in serve
    await self.serve(shutdown_event)
  File "/usr/local/lib/python3.13/dist-packages/electrumx/server/controller.py", line 141, in serve
    async with OldTaskGroup() as group:
               ~~~~~~~~~~~~^^
  File "/usr/local/lib/python3.13/dist-packages/aiorpcx/curio.py", line 304, in __aexit__
    await self.join()
  File "/usr/local/lib/python3.13/dist-packages/electrumx/lib/util.py", line 371, in join
    task.result()
    ~~~~~~~~~~~^^
  File "/usr/local/lib/python3.13/dist-packages/electrumx/server/block_processor.py", line 712, in fetch_and_process_blocks
    async with OldTaskGroup() as group:
               ~~~~~~~~~~~~^^
  File "/usr/local/lib/python3.13/dist-packages/aiorpcx/curio.py", line 304, in __aexit__
    await self.join()
  File "/usr/local/lib/python3.13/dist-packages/electrumx/lib/util.py", line 371, in join
    task.result()
    ~~~~~~~~~~~^^
  File "/usr/local/lib/python3.13/dist-packages/electrumx/server/block_processor.py", line 675, in _process_prefetched_blocks
    await self.check_and_advance_blocks(blocks)
  File "/usr/local/lib/python3.13/dist-packages/electrumx/server/block_processor.py", line 231, in check_and_advance_blocks
    blocks = [self.coin.block(raw_block, first + n)
              ~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.13/dist-packages/electrumx/lib/coins.py", line 269, in block
    txs = cls.DESERIALIZER(raw_block, start=len(header)).read_tx_block()
  File "/usr/local/lib/python3.13/dist-packages/electrumx/lib/tx.py", line 161, in read_tx_block
    return [read() for _ in range(self._read_varint())]
            ~~~~^^
  File "/usr/local/lib/python3.13/dist-packages/electrumx/lib/tx.py", line 508, in read_tx
    inputs=self._read_inputs(),       # inputs
           ~~~~~~~~~~~~~~~~~^^
  File "/usr/local/lib/python3.13/dist-packages/electrumx/lib/tx.py", line 165, in _read_inputs
    return [read_input() for i in range(self._read_varint())]
            ~~~~~~~~~~^^
  File "/usr/local/lib/python3.13/dist-packages/electrumx/lib/tx.py", line 171, in _read_input
    script=self._read_varbytes(),
           ~~~~~~~~~~~~~~~~~~~^^
  File "/usr/local/lib/python3.13/dist-packages/electrumx/lib/tx.py", line 197, in _read_varbytes
    return self._read_nbytes(self._read_varint())
           ~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.13/dist-packages/electrumx/lib/tx.py", line 193, in _read_nbytes
    assert self.binary_length >= end
           ^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError