Disable REST API before upgrading the SFR module

[Ve Con]

I read the instruction below, just want to confirm if that's true and required that I need to disable REST API before upgrading the SFR module?

https://www.cisco.com/c/en/us/td/docs/security/asa/upgrade/asa-upgrade/firepower-fmc.html#id_53912

I manage the SFR with FMC

Will upgrade from 6.1.0 to 6.2.3

ASA 5515-x with FirePOWER 

[Ve Con]

had confirmation from TAC engineer saying that it only requires for upgrading from version older than 6.1 AND upgrade to 6.1+