Check first the related counter of eNB initiated or MME initiated.
If MME initiated increase then it’s normal in 20, it’s a software bug problem.
You can talk to Ericsson PDU for more detail, and will be fixed in 21.
Has anyone changed the tilting of the cell in the 5th of march to be overshooting for example?
Check the timing advance or Out of Coverage in case TA not available.
Then I am afraid the some parameters were set to default values; such issue occurred before in different networks.
Perform parameter audit before and after the SW upgrade.
Especially for hidden parameters.
First thing there is no any other counter on 20.
Second, in your excel you mark the sub counter.
In Ericsson you can not calculate like sub counter sum equal to parents counter (abnormaleNB)
Should not be like that.
Mapped your Num formula with abnormal eNB parent counter fist in case you sure no pegging of MME release counter.
Must be same.
You should check the pmerababnormalenbpspartfailqci. If the Core is Huawei, the counter is increased by sending unspecific cause instead of normal release in path switch acknowledge.