Fr. John Boyle notes on his blog that last Sunday, Bishop Alexander Sample of Marquette, MI offered a Pontifical Low Mass in his cathedral -- its first public pre-Conciliar Latin Mass in about 40 years -- and now intends to offer this Mass in his cathedral "approximately" one Sunday a month.
To my knowledge this will make Bishop Sample the only reigning Roman Catholic bishop (aside from Msgr. Rifan of the P.A.A based in Campos) to regularly offer Mass publicly according to the 1962 Missal. (Some non-retired bishops offer it more than a few times per year, but neither monthly nor on a regular schedule.).