Question: When a Single-Cell Point-to-Multipoint (SC-PTM) capable User Equipment (UE) receives an SC-MCCH information change notification while receiving an MBMS via an SC-MRB, how does the UE acquire the new SCPTMConfiguration message if it is a Battery Life (BL) UE, UE in Coverage Enhancement (CE), or Narrowband Internet of Things (NB-IoT) UE?
Option 1: Start acquiring from the subframe in which the change notification was received.
Option 2: Acquire the SCPTMConfiguration message at the start of the next modification period upon receiving a notification that the SC-MCCH information corresponding to the service is about to be changed.
Option 3: Wait for the next repetition period of SystemInformationBlockType20 (or SystemInformationBlockType20-NB in NB-IoT).
Option 4: Immediately stop using the previous SC-MCCH information and wait for a new PDCCH scheduling command.
Explanation: For BL UEs, UEs in CE, or NB-IoT UEs receiving an MBMS service via an SC-MRB, upon notification of an impending change to the relevant SC-MCCH information, they are required to start acquiring the new SCPTMConfiguration message at the beginning of the next modification period. This ensures these UEs handle updates in a manner that balances service continuity with their operational requirements.