Massive incoming post causes delay. Can debate the central point of the letter: the inadequacy of the New Order Mass compared to the Tridentine Mass. Vatican II debated extensively and profoundly and from there was promulgated the "Constitution of the Sacred Piturgy" in 1963 from which came the April 1969 Apostolic letter of Pope Paul. Fr Baker has known of the1970 Hierarchy directive and has deliberately put his Bishop in an impossible position but is following Canon Law; he could have acted summarily.
The proposed Mass has no ecclesiastical authority - Fr Baker has not sought leave to offer Mass. Despite Fr Baker's defence of following his conscience he has overlooked the duty to educate his conscience - cites a few examples. Bishop says the Fr Baker is neglecting the guidance of Vatican II, the Pope, Bishop Grant and Bishop Clark. Even if you cannot accept these, consider deeply before leaving Downham Market to share your personal difficulties in other dioceses.