and, just so you know, if you put it in offline mode and then turn it off, it will be in offline mode when you turn it on again.

so, i guess, if you want it to always turn on in offline mode, always set it to offline mode before you shut down. or, if you're feeling adventurous, you could try writing a script that would switch into offline mode and then shut down, and then you could always use that script to shut down instead of using the power button. practically speaking, that wouldn't be worth the time, because it only takes a few clicks to do that manually, BUT if you're a tinkerer, it's worth giving a try.

sorry for being so long-winded, but just one more thing: shutting down the tablet is actually somewhat discouraged around here. it consumes a lot of energy to boot up, PLUS when the device goes to standby (which is automatic), it uses barely any energy. mine hasn't been shut down in over a month. also, i always put it in offline mode at the end of the day to save energy.