https://sec.cloudapps.cisco.com/security/center/resources/asa_ftd_attacks_event_responseIf you are on an older version of code you could have a lengthy upgrade process.
If you mean 7.2.5 to 7.2.6 then yes you can make that jump with no issue. Make sure to do both the FMC and the FTDs. But I think your version can differ depending on which firewall you have. If you have support on that device I recommend opening a TA...