Month title adding day of week and date.... July becomes Tuesday, July 1

This happened to us as well when date module was updated from 2.7 to 2.8 :/

Same for us after upgrade date from 2.7 to 2.8
In the changes i saw

Issue #355058 by Grimreaper | prunelle: Hardcoded day/month/week output format for theme_date_nav_title().

#2294973: Date format in calendar title remains default (e.g., month view date shows as July 1, 2014) is the more exact duplicate of this. I had the same problem. Code in date_views.install that sets some variables does not get run on update. I did the equivalent of that code from drush

drush vset date_views_month_format_with_year 'F Y'
drush vset date_views_month_format_without_year 'F'
drush vset date_views_day_format_with_year 'l, F j, Y'
drush vset date_views_day_format_without_year  'l, F j'
drush vset date_views_week_format_with_year  'F j, Y'
drush vset date_views_week_format_without_year 'F j'