Attachment / File Destination for uploads in a form

I have created a form that requires users to upload files

attachments:
          label: Attachments
          type: file
          multiple: true
          limit: 10
          destination: 'user/data/ServiceForm/files/{{ form.value.project_name|e }}'

I have used the destination field, but it will typically only save in one single folder,

I am trying to use a form value to create a custom folder within the user data folder

this code above just created a folder called '{{ form.value.project_name|e }}' instead of using the form value of the project name

this of course didn't work, but any clever people out there know how this could be achieved or if I am missing something simple.

Thanks

update:

tried adding

process:
  twig: true
cache_enable: false

but didnt work

@dean_007, The value of 'destination' is not being processed using Twig. It is used 'as is'.

Using a plugin you might be able to process the Twig string yourself during one of the events raised by the Form plugin and update the value of 'destination' field before the file is being saved.