HELP> our hemlock pine home in sw pennslyvania is about 33 years old and in need of exterior cleaning staining, ect.. we hired a co, they used mixture of bleach & tsp and pressure washed entire house looks beautiful, then they used cedar dynamite caulk, also looks beautiful, PROBLEM when they started to brush on SIKKENS SRD in NATURAL OAK it is turning all the beautifull honey oak colored wood to an UGLY DARK BROWN/BLACK…what do we do?