sorry, but I have to mention that there is no “Bes” in german music at all, there is only “H”, “B” and “Heses” (with double flat - not “Bes” or “Beses”) for single notes! I stumbled over it when I changed chord symbols in one flow to german suffixes… You can use “Bes” for the plural of more than one “B” though. As well, when you want to make it very clear that you want to use the “H” with a flat, you could use “Be” for “B”, but it is not necessary to do so since this would be rather phonetically oriented. With chord symbols, it might be better for clarification to show the letter B with the flat, but that is a question of taste, so perhaps both possibilities (Bb and B) should be offered in Dorico (a mixture of german suffixes and english/american symbols).
The search with the dorfor method dit not yield any results that this was mentioned in the forum before, so forgive me if I post this perhaps again. (I know that someone already mentioned that the instrument names should only have H or B added, not both).