After upgrading drupal core from 8.3.9 to 8.6.1, behat from 3.1.0 to 3.3.1 and drupal-driver from 1.2.x-dev to 2.0.x-dev, behat tests are failing for dates of 'Date only' date type. D8 has two date types 'Date and time' and 'Date only' for 'Date' field. There is no issue with 'Date and time' date type. It looks drupal-driver is not able to create dates of 'Date only' date type. I have tried different date formats but none is working.
I can create pages with 'Date only' dates and they appear correctly on the page in the desired format, it is just the behat test which is failing to generate it on the page. It looks DatetimeHandler class in not handling 'Date only' date type.

My test.feature looks like (field_publication_date is 'Date only' date)
@api
Feature: I can see publication data on publication page.
Background:
Given I am an anonymous user
And "publication" content:
| title | moderation_state | field_publication_author | field_publication_date |
| test-title | published | test-author | 2016-09-01 |

Scenario: I can see the correct publication data
Given I am on "/test-title"
And I should see the text "test-author"
And I should see the text "September 2016"

Error:
001 Scenario: I can see publication data on publication page # features/publication.feature:35 And I should see the text "September 2016" # features/publication.feature:44 The text "September 2016" was not found anywhere in the text of the current page. (Behat\Mink\Exception\ResponseTextException)

Format tried:
2016-09-01, 2016/09/01, 01/09/2016, 01-09-2016, 2016-09-01T05:00:00, 2016-09-01 12:12:12, 1 minutes ago etc.
As I said it doesn't looks like format issue. Behat is not able to create date of 'Date only' type. I have also tried putting break just before date test statement to see if date is being created in different format other than expected but date field along with its label is not at all present on the page.

Versions used:

behat/behat:    v3.3.1 
behat/gherkin:    v4.5.1 
behat/mink:    v1.7.1 
drupal/drupal-driver:   2.0.x-dev
drupal/core:    8.6.1

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