A potentially relevant though likely unrelated error:
Feb 3 23:47:11 sentry-worker-6869d7c6f8-m28zj sentry-worker ERROR 06:47:11 [ERROR] celery.app.trace: Task sentry.tasks.email.send_email[28200cdb-1316-42f5-b3df-cadf53d54f62] raised unexpected: IndexError('string index out of range',) (data={'hostname': 'sentry-worker-6869d7c6f8-m28zj', 'id': '28200cdb-1316-42f5-b3df-cadf53d54f62', 'name': 'sentry.tasks.email.send_email', 'exc': "IndexError('string index out of range',)", 'traceback': 'Traceback (most recent call last):\n File "/usr/local/lib/python3.6/site-packages/celery/app/trace.py", line 412, in trace_task\n R = retval = fun(*args, **kwargs)\n File "/usr/local/lib/python3.6/site-packages/celery/app/trace.py", line 704, in __protected_call__\n return self.run(*args, **kwargs)\n File "/usr/local/lib/python3.6/site-packages/sentry_sdk/integrations/celery.py", line 197, in _inner\n reraise(*exc_info)\n File "/usr/local/lib/python3.6/site-packages/sentry_sdk/_compat.py", line 54, in reraise\n raise value\n File "/usr/local/lib/python3.6/site-packages/sentry_sdk/integrations/celery.py", line 192, in _inner\n return f(*args, **kwargs)\n File "/usr/local/lib/python3.6/site-packages/sentry/tasks/base.py", line 48, in _wrapped\n result = func(*args, **kwargs)\n File "/usr/local/lib/python3.6/site-packages/sentry/tasks/email.py", line 76, in send_email\n send_messages([message])\n File "/usr/local/lib/python3.6/site-packages/sentry/utils/email.py", line 408, in send_messages\n sent = connection.send_messages(messages)\n File "/usr/local/lib/python3.6/site-packages/django/core/mail/backends/smtp.py", line 111, in send_messages\n sent = self._send(message)\n File "/usr/local/lib/python3.6/site-packages/django/core/mail/backends/smtp.py", line 123, in _send\n from_email = sanitize_address(email_message.from_email, encoding)\n File "/usr/local/lib/python3.6/site-packages/django/core/mail/message.py", line 161, in sanitize_address\n address = Address(nm, addr_spec=addr)\n File "/usr/local/lib/python3.6/email/headerregistry.py", line 42, in __init__\n a_s, rest = parser.get_addr_spec(addr_spec)\n File "/usr/local/lib/python3.6/email/_header_value_parser.py", line 1585, in get_addr_spec\n token, value = get_local_part(value)\n File "/usr/local/lib/python3.6/email/_header_value_parser.py", line 1395, in get_local_part\n if value[0] in CFWS_LEADER:\nIndexError: string index out of range\n', 'args': '()', 'kwargs': "{'message': <django.core.mail.message.EmailMultiAlternatives object at 0x7f1ebc2d0710>}", 'description': 'raised unexpected', 'internal': False})