Questions about bleach bath after box dye

If you are trying to prevent damage you should wait a month before you bleach bath.
Fine to use H&S and bleach over coconut oil.
If you want to use an oxidative toner you should treat it as another permanent dye and wait a full month ideally. I don't like oxidative toners for this reason. They work just as well with 10 vol peroxide, but doing another chemical process over freshly bleached hair is a bad idea.
If you get to the inside of a banana yellow, you can tone to whatever shade of blonde you want with direct dyes, no need for that final chemical process.
Oxidative toners fade just as quickly, so you will be adding to the damage every time you need to top up the colour.

Thanks for your help!  I haven't seen any hair dyes that give an actual platinum/silver color so I was going for a toner.  Are there some out there?

ETA - In case I'm not being clear about what I mean there.  I've seen some "platinum" dyes but they look more pale yellow to me than actual platinum/silver. 

Yes, you can tone your hair to silver without using oxidative dyes. Pravana silver is a lovely colour that can be diluted to a pastel, almost white shade or used neat for a gunmetal/platinum/grey shade. There are several, but it really depends on what colour your base is.

That's awesome, thank you!  I had heard of Pravana before but have no experience with that brand, I will definitely look into it!  I appreciate the help 🙂  I've never been blonde before, let alone platinum, so this is a new experience!