The item should be in the 'railway' lost property system if it has been handed in. For TPE, that is probably almost as difficult to work out as the bus operator (could be Northern, Scotrail, LNER, I assume depending where the item was found). On all the TOCs that I have worked for on rail replacement, unclaimed lost property found on buses is handed in to the nearest staffed station on the route and then goes into the usual lost process for property left on a train. If the loss is recognised quickly enough and there is controller at the station, the controller will ask their colleagues on the route if the missing item has been found and handed to them or for the bus to be searched for the item when it reaches the next station with a controller. Arrangements are then made to re-unite the item with the owner by sending it back with the driver of a service or allowing the owner to travel to the station where the item has been handed in. It is not a perfect system but it can work really well. Drivers should check their vehicles at the end of each journey but don't always do it. They are more likely to check their vehicle at the end of shift before returning to the yard. The aim is to ensure that lost property does not end up in the bus operator's depot whch could be miles away. Realistically, your chances of finding anything which has ended up with the bus operator are going to be very low unless you can identify the operator on the day of travel with a bus coordinator. After the day of travel or even on the day of travel, it is very unlikely that TOC staff would know who operated the relevant replacement service. It would be sheer luck that someone saw that journey and remembered the operator. I assume that TOCs are provided with the information about which company will be operating each service but it will have very little relevance to their work and it probably needs to be decoded from the timetable. Controllers are generally provided with the information in a accessible form but once their shift is over, they are effectively uncontactable by any TOC staff.