I fired it up the day before it left the shop and didn't bother to oil the inside as I figured they would be using it straight away and if we needed to change anything it is clean.
We were thrashing on it till 5 mins before the flat bed arrived to finish it and now it is sitting for months.
This last weekend I had another customer that bought a horizontal cooker ask me for cooking advice.
He was complaining that he couldn't get it up to temp and there was a lot of smoke coming out the door. He sent me a photo of a barely smoldering fire. He had the air damper mostly closed and the chimney flap fully shut! :o