And there's still this much battery left. A surprise to be sure, but a welcome one. I wasn't expecting it to still have any power left at all. I suppose with the sim out, all it was doing was powering the clock, but still! Unfortunately, I've had to retire it as my network won't connect on it anymore.
Without a SIM it doesn't use much power at all. Even an Android phone will last a month on standby if you just leave it on the table with all connectivity disabled.
I remember back in 1998 when Philips introduced GSM phones with 300+ hours standby battery life (with a bigger battery). Until then it wasn't uncommon for phones to last 8 to 20 hours. Then others figured out the same, but long standby was never practical unless you really just leave a phone on a table.