In the final scene in the depot, you can clearly see that it rains only in that area.
Locations for the drug stashes are sent to the Metropolitan Police, however the filming took place on an estate on Middlesex Street, E1 which is City of London Police territory.
Around 45:00, iBoy makes up several small packages of drugs with smiley faces on them that he took from the gang's hideout; in doing so, he is not wearing any gloves. When the forensics team finds them, they are wearing gloves. iBoy's fingerprints are all over them, making him the prime suspect instead of the gang members whom he is trying to frame.