Yes, you can write and generate a static website while offline and publish it later when you have connectivity.

You can also read articles from any Planet you follow while offline, as they are stored in the local repo. For example, if you fetched the latest articles from vitalik.eth, you can read them during a long flight without Wi-Fi.

When you start Planet in an offline environment, the IPFS status area shows Online (0) indicating that no peers are currently connected.

These features are fully functional offline:

• Write or edit a post
• Generate a website
• Read retrieved articles from the Planets you are following

These features need connectivity:

• Publish: Write CID to an IPNS and broadcast the update to your IPFS peers
• Check for Update: Find new posts, or a new version of the app, from the Internet
• Aggregation: Fetch posts from other IPNS, ENS, or RSS addresses