Recovering instance in v2.6.0a (only) via REST API may result in error 500 and the "AttributeError: 'unicode' object has no attribute 'aws_region'" exception

Recovering instance in v2.6.0a (only) via REST API may result in error 500 and the "AttributeError: 'unicode' object has no attribute 'aws_region'" exception

The problem is on v2.6.0a, in REST, recovery might fail with error 500 and in the CPM UI it looks in progress.

The following errors may be logged:
ERROR    MainThread   cpmrequest.py   151   call                                          API Request error: 500
ERROR    MainThread   cpmrequest.py   152   call                                          <!DOCTYPE html>
<html>
<head>
<title>
CPM Cloud Protection Manager | 500
</title>
</head>
<body>
<h1>A Problem Occurred (500)</h1>
<h2><b>Sorry, but there was an error while processing your request</b></h2>

and following in server logs
ERROR:  handle_uncaught_exception(exception.py:135)  Internal Server Error: /api/backups/133/snapshots/instances/108/recover/
Traceback (most recent call last):
  File "/opt/n2wsoftware/python/lib/python2.7/site-packages/django/core/handlers/exception.py", line 41, in inner
    response = get_response(request)
  File "/opt/n2wsoftware/python/lib/python2.7/site-packages/django/core/handlers/base.py", line 187, in _get_response
    response = self.process_exception_by_middleware(e, request)
  File "/opt/n2wsoftware/python/lib/python2.7/site-packages/django/core/handlers/base.py", line 185, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "/opt/n2wsoftware/python/lib/python2.7/site-packages/django/views/decorators/csrf.py", line 58, in wrapped_view
    return view_func(*args, **kwargs)
  File "/opt/n2wsoftware/python/lib/python2.7/site-packages/rest_framework/viewsets.py", line 95, in view
    return self.dispatch(request, *args, **kwargs)
  File "/opt/n2wsoftware/python/lib/python2.7/site-packages/rest_framework/views.py", line 494, in dispatch
    response = self.handle_exception(exc)
  File "/opt/n2wsoftware/python/lib/python2.7/site-packages/rest_framework/views.py", line 454, in handle_exception
    self.raise_uncaught_exception(exc)
  File "/opt/n2wsoftware/python/lib/python2.7/site-packages/rest_framework/views.py", line 491, in dispatch
    response = handler(request, *args, **kwargs)
  File "./common/annotations.py", line 98, in log
  File "./cpmserver/api/v1_0/handlers/__init__.py", line 275, in create
  File "./cpmserver/api/v1_0/handlers/recovery_handlers.py", line 660, in perform_create
  File "./common/annotations.py", line 98, in log
  File "./cpmserver/cpm/model_operations/recovery_operations.py", line 1489, in execute
  File "./cpmserver/cpm/model_operations/recovery_operations.py", line 1527, in recover
  File "./cpmserver/cpm/model_operations/recovery_operations.py", line 2556, in get_default_to_region
AttributeError: 'unicode' object has no attribute 'aws_region'
If you encounter this errors, please upgrade to the latest  2.X.X version.

Reference defect number – N2WS-8473
Link to Release Notes – release notes for the latest v2-6-x cpm release