Process for upgrading across multiple versions of 3scale API Management 2

Issue

• Looking for a way to upgrade from 2.0 to 2.3.
• Is it possible to upgrade from 2.2 straight to 2.5?
• Do we need to do incremental upgrades for 2.0 to 2.1, 2.1 to 2.2, then 2.2 to 2.3?
• Do we need to go 2.4 -> 2.5 -> 2.6 or can we go directly to 2.6?
• How to upgrade from 2.8 to 2.9.1
• What steps and considerations for pre and post upgrade
• Will updating the channel take care of upgrade?
• Can a single or non-sequential upgrade be performed to move across multiple major/minor versions?