I made a usefull spreadsheet (i upgraded the one of snowman25)
here in you can find the offline collector and the time you need to be offline.
the link: https://docs.google.com/spreadsheets/d/1m0jtBiaxdkWVQIFP0qYWueJzYItUTI0exNWiMljrpWA/edit?usp=sharing
And what exactly does having it made in scratch change?