I was more confused by "...adjacent to the west wall at the western end of the upper level..." As opposed to the bins located opposite the east wall at the northern end of the lower level, I suppose. Have fun!
Funnily enough wcs, I had to re-read that bit three times before I was satisfied I understood what was meant, and I live here!
Clearly your fellow residents have achieved a certain level of education and understand the instructions. What the less educated such as myself may have picked up, do nothing with rubbish between the 11th and 14th.
'(F)rom Monday 11th April until Friday 15th April' seemed clear to me Andrew. Nevertheless there will be probably be as many interpretations as residents.