* create method to test whether we are currently in the crossover period and associated tests
* update copy, use method for testing whether we are in the crossover period, remove focus from test file
* reuse existing method to determine whether we are in a collection period
* use the existing method and update validations
* fix test broken by changes
* update location in same way as scheme
* create method on FormHandler that finds the start date of the earliest collection period
* ensure that default deactivation and reactivation dates also reflect the changes
* create tests for the new validations
* lint correction
* minor copy change
* minor logic change
* amend naming error after rebase conflict
remove test that is no longer correct after change on another branch to functionality
update a test after a copy change