This is a tutorial on how to bypass iCloud on iPad Air 4G, after following this guide your iPad cellular shouldn’t work but wifi, bluethoot and gps will remain working.
First thing is to disassemble your locked iPad Air since this is a hardware method.
Video made by Powerbook Medic
Disconnect the battery and take out the motherboard.
On the iPad Air 4G Model A1475 you must only remove the resistors r1506.
Connect your iPad to itunes
iPad will automatically enter in DFU mode.
You must restore your iPad Mini using iPad Mini wifi model firmware and follow the steps to activate it.
When successfully done, turn off the automatic firmware update.
As mentioned before this instructions are only for iPad Air 4G model A1475.