In the current Salto integration with Mews, Mews only sends one room number/lock id to be encoded in Salto. This presents an operational challenge for properties that have the following room structure:

6228 - main suite (parent space)
230 - private room for 2 persons (child space)
228 - dorm room with 4 beds (child space with 4 additional child spaces nested)
228-1,2,3,4 - four separate dorm beds

230 and 228 can be sold separately, as is any of the four beds. A party of 6 can also book the entire suite 6228.

In the latter case, a key card encoded for all 6 guests with a reservation occupying 6228 should include access to both 230 and 228.

In Salto, it is currently not possible to manage mapping 6228 with clients 228 and 230 (i.e. key card encoded for 6228 automatically comes with access to the two child spaces).

It is recommended that Mews extends key creation message to include "Second room to be opened by the card." in Field 4 described in the table under the section "Command ‘CN’: encode a new guest card." as found in the SALTO Industry Standad PMS Protocol documentation