Clarification needed for a student project

Hello, I’m a digital engineer student and I’m working on a project in which I use IPFS and Blockchain. Here are my specifications:

  • People can create some JSON files in a web application and publish it.
  • They can retrieve, modify and delete their files with IPNS.
  • The JSON files are be using in a mobile app in which everyone can read them.
    => Read-Write permission for the authors and Read-Only permission for the others.

Here is the problem. The creators will use IPFS from a browser, without necessarily having a node running 24/7. My idea is to connect all users together, so that files are always accessible, while keeping write privileges. However is-it possible ?
If people use the IPNS address to get a file but the node is offline, is it still possible to provide the file through other nodes in the network?
Many questions, I know!

Thank you in advance for your advice !