iPhone unavailable Emergency or Erase options only

iPhone 7 in my back pocket while doing diy. Not sure if it was trying to unlock itself & putting in random digits (like a butt dial) or if it was just a fault (some people have reported this happening overnight) but the screen says iPhone unavailable with only Emergency or Erase as only options. I still know my passcode but am unable to enter it… surely I don’t have to erase my iPhone & lose all my unbacked-up data do I ? I have a lot of recent holiday pics I have not yet backed-up & I don’t want to lose them.

Any help (other than erase & start again) most welcome. Thanks