Upgrade bench from v12 to v14

Hi Everyone !
I have a bench with a site with ERPNext v12 and a custom app installed. The custom app heavily customize the ERPNext behaviour
i am searching for a good guide to upgrade my site and custom app to v14 could someone help ?

Thanks

@Steven_Athouel take backups for everything . if you can the entire system . then switch to v13 . then v14 . (not at the same time.).
or create a new v14 system and take your backup and app there . the system will fix the database changes automatically but you will need to do some work yourself especially in the custom app

Hi, thank you for your reply !
what do you mean by switching from v12 to v13 ?

  1. running bench update on v12 then
  2. switch frappe and erp repo to version-13 branch then
  3. run bench update
    ?
    the bench update will upgrade my db but i know that the dependancies changes between v12, v13 and v14 i.e python and node version so i don’t think that simply update will work

@Steven_Athouel the command is bench switch-to-branch . and it will download all packages . ans also you can try teh second method