Good luck with the dealer. I found rust within 3 months of buying the car, told to buy a touch up pen. Complaints got nowhere. I have also found the same rust spots on the same panel. Over the time I have owned the car, I have realised that it has been in a few knocks. It is now obvious that the rear door had been worked on and as said an angle grinder was used and the 'crud'( thanks Culzean) had not been cleaned off. Consequently the filings had rusted, along the panel securing the hinges, which incidentally are rusting around the pins. Some rust curer and silicone spray has halted this.
How do I know an angle grinder had been used, well, recently the hatch door window was replaced and when I took the cover off the rear wiper, there on the underneath was clear marks caused by an angle grinder.
I cannot find out who did the repairs but if they are the result of an approved Honda repair, then I am appalled. Last Sunday, when trying to sort out the stuck rear door window, I saw where paintwork had been rubbed down and not sprayed. The door hinge bolts are all rusting, where spanners have been used on them.
The car allegedly had a 2 yr Honda extended warranty. I think the paper it was printed on was worth more.