Sorry if this isn't the right place to ask, but if anyone knows, it would be you :) I know there are several former Phantoms/Raouls who became Andres, but are there any who became Firmins?
I am guessing this is in contect of Earl Carpenter playing André in the current Italian non-replica production. Because that is indeed a fairly common combo, to have an actor play André and the Phantom or Raoul. Their range and voice type seems to correspond well, as does the body type. Thus, the list of people covering two or more of these roles is a fairly long one.
But FIRMIN and The Phantom or Raoul? Rarer combo. I guess the tendency to type cast Firmin as sturdier and sometimes older makes him a less typical candidate for the other roles. More often than not we're talking a u/s Firmin, or someome returning to the role after many years. But it's totally not set in stone, ad this list will show:
David Huneyager: Principal Firmin in Chicago and the US Tour 1990-1996, principal Firmin and u/s Phantom in Hamburg 1997-1999.
Jørn Pedersen: Principal Firmin in Copenhagen 2002, alternate Phantom in Copenhagen 2002, and u/s 2000-2003.
Jun Sawaki: Principal Phantom (shared) in Nagoya, Osaka and Tokyo 1990-1992 and in Nagoya and Tokyo 1997 -1999, as well as principal Firmin (shared) in Tokyo 1992.
Tim Morgan: u/s Phantom (2002) and Firmin (2002-2020?) in the original West End production and u/s Firmin in the West End revival 2021-2023.
Stephen John Davis: u/s Firmin in West End 2009, u/s Phantom in West End 2009-2010. He was also principal Buquet! A quite unusual combo of roles.
Toshihide Mura: Principal Firmin (shared) in Tokyo 1992 and in Tokyo 2020-2023, principal Phantom (shared) in Nagoya and Tokyo 1997-1999, Hiroshima 2001, Tokyo 2005-2007, Nagoya 2009-2010.
Sebastian Lamberth: Principal Firmin and u/s Raoul in the non-replica Kristianstad production in Sweden 2023.
Michael Cormick: Principal Raoul in the original West End production 1988-1990, principal Firmin in the non-replica Sydney Harbour production in 2022. He was furthermore principal Phantom in a community theatre production in Canberra 2013.
As always, it's not a complete list, just those I could think of. Feel free to add others in the comments :)
(I did originally also list Young-Seok Yoon, but he went from playing the Phantom to ANDRÉ, not Firmin)