To obtain the new BU Harvard style, you can either
a) Re-install EndNote 20 from AppsAnywhere (applies to Windows machines, BU or personal, and will be available shortly - if your references still output with [online] please try re-installing at a later date as it may take a few days for the changes to happen)
b) Add the new style from the BU EndNote desktop help pages here (applies to Windows machines, BU or personal and also Macs, BU or personal)
https://libguides.bournemouth.ac.uk/endnotedesktop/tips1
c) If you have a BU Mac and install EndNote from the BU software menu, we will shortly have EndNote 21 available with has the new BU Harvard style included