A 67‑year‑old man with GOLD stage II COPD (FEV₁ 60% predicted) presents with increasing breathlessness, cough and purulent sputum for 4 days. He has used a short‑acting beta agonist as required but no long‑acting inhalers. He has had two moderate exacerbations in the past year requiring oral steroids and antibiotics. According to COPD‑X and Australian practice, what is the most appropriate change to his long‑term pharmacological management?