My long standing tenants are being deeply adversely affected by an Airbnb property adjacent . I am very concerned I might lose valued tenants as a consequence of noise and disturbance . The property let as an Airbnb was until recently just residential use . Does Brighton council require there to be planning application for change of use to permit an Airbnb ? I’m fairly sure there has been no such application if so
Contact the council and ask. Tell them what the issue is. Also report the issue to Airbnb. You will need to be clear about what noise and what disturbance.
Would it be an idea to contact the property owner and discuss the issue, possible remedy? For example they could have insulation backed plasterboard installed on the shared wall between your and their property (lounge?), it’s not that expensive. You could find out their details using the Land Registry web site, doing a search by property address. It was £6-7 the last time I needed to check who owns the freehold of a property.
Airbnb take noise complaints about their owners properties quite seriously so I would definitely consider reporting the issue to Airbnb if you can. They will put the onus on the owner to make sure their guests comply with the rules or risk being booted from the platform so should be enough to get them to act.