You can create 'Recurring Shifts' within your portal, which will enable you to establish a method for your Users to apply for all linked shifts together with ease, as well as still apply independently depending on your desired outcome.
To link your Recurring Shifts you will need to first create shifts using a Shift Pattern.
Once done, within your Event, select 'Actions' and Create Shifts from Pattern.
In the pop up, select Link Shifts.
You will be prompted to apply a naming convention. Please note, the Name here is simply a common name for this group of linked shifts.
Click Import.
Overall settings for Recurring Shifts:
Within 'Organization Settings' under the 'Events' tab, you will have unique rules which apply specifically to linked, recurring shifts and how you wish your users to interact with them.
You can ensure users can apply for all linked shifts together or if they can pick one shift from a group of linked shifts.
There are some caveats within your settings which would impact this flow - As an example;
A) If there are 5 shifts that are linked together, but one shift demand has been met - the user will be applied to the remaining shifts, and the demand number will prevent a further application.
B) If there are 5 shifts that are linked together, but the user is not available or has a clash due to another confirmed shift, then the user cannot apply for any shifts that are linked together
Being able to adjust the above setting rules will allow you to define exactly what you want to occur.