Here is what the envelopes looked like when they came back to me. It took around 2 working days for them to be delivered and they all came at the same time (since I posted them all at the same time, so this comes as no surprise) All of them have stamps in the upper right hand corner, indicating where it was sorted (with the exception of the drug image, which is just a cut off circular stamp). The gun and the poison image both have orange stripes on the envelopes, indicating it was machine sorted. I believe that there might have been a problem with the drug one and it had to be hand sorted rather than going through a machine and that’s why its different. The corners seem slightly scuffed but other than that there doesn’t seem to be too much damage to the envelopes.
For next time I would like to be able to make the address look more pleasing. I will try using a typewriter and printer to see if the images turn out well. I think my handwriting ruins the overall look of the envelopes. The random placement of the address as opposed to it being written in the centre didn’t work out very well for me either, so I will stick to the traditional position from now on. Since they all came back together, I will be sending future letters from different post boxes to see if they will be delivered on different days and in different conditions.