Not sure if this has been done before. Has to be a significant new lineup change, not just a new bassist/drummer (sorry bassists and drummers!). Really looking for ones where the band sound and identity was rebooted and maybe even had a new creative force. First examples I thought of: Fleetwood Mac 1975, bringing in Buckingham and Nicks Deep Purple In Rock, bringing in Gillan and Glover. Doesn't have to be two new members like my examples; could be one but has to be a significant change that gave the first album they did a feel of it being a 'debut'.