When selecting some portion of text for overtyping with new information, Evernote 6.10 often simply ignores the previous selection, and inserts the new material before the selection, causing typographical errors in the resultant document. This is absolutely unexpected behaviour, and simply adds to editing frustration.
Whenever I try to replicate this behaviour, I am not able to consistently replicate. However, mostly, it seems to occur, when having typed something, I choose to replace this with new information. My steps in maOS Sierra are:
Type some information, half a dozen characters are all that is necessary, Makes difference whether bullets or normal paragraph
Hold SHIFT + COMMAND and press Left Arrow to select entire line, OR, hold SHIFT + OPTION and press Left Arrow to select by words
With text highlighted, now enter replacement text.
NOTICE: The previous information remains, and is preceded by the new information without any adjoining space.
Evernote for iOS does not exhibit this behaviour, but operates exactly as expected, overtyping the selected material with the new information.