When to refer to a Periodontist (hand scale)

Since my return to work following COVID-19, we have not been doing any AGPs - so hand scale only. Many of our clients see a periodontist every 2nd hygiene appointment. My employer recently shared an article with me comparing hand scale to ultrasonic debridement, which concluded that an adequate clean is completely achievable with hand scaling. While I agree that it is possible, I know I can adequately reach 6-7mm pockets with my ultrasonic scaler yet I struggle to get the same clean with hand scaling. I wonder if referral to perio should be done more proactively, say in cases of stage 2+ periodontitis.