SRVCC Preparation Failures increased after 3G Shutdown

Hi All,
We have done 3G U900 shutdown in one city.
Post that the SRVCC Preparation Failures towards GERAN has increased heavily.
Vendor is Ericsson.
Any suggestion on troubleshooting?

Yes check below things:

  1. Definition of 2G neighbours in worst cells, because previously with low number attpt failure might not be visible
  2. LAC-TAC combination at MME level. Now instead of 3G LAC, 2G LAC should be there in definition.
  3. SRVCC threshold & hysteris parameters.

Also need to check required features at BSC end.

Can you list out the features to check in BSC end for SRVCC to happen?
LTE end, srvcc to geran is enabled, activated and operable.

It must be there before also.
Only change happened that now footprint changes with 2G.

Update: We took reference from our collegues working on different operator who did same activity, and we are deleting and recreating all lte to geran relations with anr switchoff/on in few trial sites.
We will be monitoring if any benefits observed or not.