Version upgrade from 12.01 to 12.55

Hi HPE PC Experts,

Could you please provide any version upgrade plans or check lists for migration 12.01 version to 12.55 migration. What are the things need to look out for, best practices need to be followed, any help in this regard highly appreciated. Thanks.

Env Architecture:

ALM Servers - (OS Widows 2012 R2) (149 GB, 16 GB MEM, 4 CPU)

PC Servers - (OS Widows 2012 R2) (149 GB, 16 GB MEM, 4 CPU)

DB Servers -  SQL server 2016

File Servers - Windows 12, 5 TB

(Linux Docker Generator) (OS RHEL 7) (100 GB, 16 GB MEM, 4 CPU)

Regards,
Bala.