2230207 - Error 8204 on system catalog id 58 after downgrade - SAP ASE

After downgrading server, DBCC check failed with following messages.

Starting dbcc checkstorage for ASE_servername.model at Sat Oct 10 06:28:21 HKT 2015

Checking model: Logical pagesize is 2048 bytes

Msg 8204, Level 20, State 5:
Server 'ASE_servername', Line 1:

Expected to receive system catalog id. Instead 58 was received.
DBCC CHECKSTORAGE for database 'model' encountered an error. Some
results may not be available. Correct the problems reported and
reexecute the CHECKSTORAGE command.

Verifying faults for 'model'.

DBCC CHECKVERIFY for database 'model' sequence 162 completed at Oct 10
2015 6:31AM. 0 suspect conditions considered, 0 identified as faults,
0 identified as harmless, and 0 could not be checked. 0 objects could
not be checked.

Deleting results of DBCC operations completed before Oct 3 2015 6:30AM on database model.

(return status = 0)

Completed dbcc checkstorage for ASE_servername.model at Sat Oct 10 06:31:13 HKT 2015

SAP Adaptive Server Enterprise (ASE) 15.7

8204, 2513, 15018, sysdams, 58, downgrade , KBA , BC-SYB-ASE , Sybase ASE Database Platform (non Business Suite) , Problem