if you have ROM: 15.0(1r)SG1 - Straight upgrade.
Not sure why you are under the impression that the response BB provided does not make sense. The answer he gave you in his first post is correct. You can jump directly from 3.02.02 to 3.11.01. Just make sure to do a complete backup of your config before the upgrade and do the upgrade in a maintenance window as it does require downtime and in some cases, you may lose part of the config.
First, upgrade the ROMMON to, a minimum, 15.0(1R)SG11 (Upgrading the System Software). If possible, go straight to 15.0(1r)SG16
Next, why 3.11.1? This version has been released since December 2019.
If TAC has "recommended" 3.11.1 then ask them about the more recently-released 3.11.4 (released 22 March 2021).
Next, upgrading from 3.2.X to 3.11.X can be done.
And finally, a working upgrade process can be found HERE.