We have the case of two components for date and timeslot (hour and minutes in quarters of :00/:15/:30/:45).
Here is how it looks like if someone uses a single component for each and uses the native components of what the framework supports
On the other hand there are mockups which are suggestions to increase usability. This is the custom component for the hour selector:
and this is the mockup for the custom component for picking the date:
Also will the date selector be more usable if the form contains both the native and custom suggestion?
I could give you more context but there is some confidentiality. Go ahead and ask freely though.