I experienced one of the most frightening situations a Lightning user can go through.

After a recent iOS update and a ZEUS app update, my embedded LND node inside ZEUS simply vanished. The wallet would not load. My previously configured NWC connections were gone. Most importantly, the majority of my Lightning funds were inside that embedded node.

For a moment, I truly thought I had lost everything.

Fortunately, I had my seed backed up. On top of that, ZEUS had been automatically backing up my SCB to Olympus. I cleared all walllet data, and when I restored the wallet, the SCB was retrieved and the node immediately went into recovery mode, triggering force closures of all my existing channels. After the timelocks cleared, I was able to sweep all of my funds back on-chain safely.

I’m not sure whether this was a ZEUS issue or something caused by iOS, but as far as I know, iOS treats apps as disposable and can make app’s data container invalidated or recreated after system update?

For most apps, this can harmless. But for a Lightning node, losing that data is a very serious event because of the channel state.

Today, I learned this lesson in safe way.

Always back up your seed.
Always back up your channel state.