In a patient with intermediate risk castration sensitive prostate cancer S/P prostectomy and now with biochemical recurrence + regional lymph node involvement 8 months post RP, would you do hormonal therapy (ADT or ADT+Abiraterone) with or without EBRT?

Yes, node positive (N1 M0) patients such as this were eligible for the STAMPEDE trial of ADT +\- abiraterone even in the relapsed setting after local therapy. These patients have both a disease free and overall survival advantage with abiraterone. See NCCN guidelines 2019.