can you see the pads through the holes in the wheels? If you can, you should be able to see for yourself how much friction material is left on them, it's the layer that pushes onto the disc, there only needs to be enough material on them to last till May, then you can get whatever pads you want fitted by anyone you want without worrying about the warranty. you can tell when they actually wear out because they will make a racket when applied.
Honda fixed price for a set of brake pads supplied and fitted is £131, the last set I had fitted, (not Honda pads) at an independent garage (about 7 years ago) they were £75, so its not going to cost you crazy money if you decide to go to a Honda dealer for peace of mind over the warranty.