Having some issues with Tax Codes not getting filled in when clicking the Bill button on an Item Fulfillment or Order Confirmation. The Invoice form loads, and all line items show Tax Code as required, but the Tax Codes are all empty.

File a case with support. This one doesnt sound like a config issue

Good question! Switching forms doesn't change the behavior though. Just spent a half hour with accounting and our other NetSuite developer; they indicate this seems to have happened after the 2020.2 update. Prior to that they state the Tax Codes were never a problem. Here's the annoying bit: if you edit an Invoice line item or add a line item, the Tax Code gets filled in correctly. It's only the freshly-transformed version of the Invoice that's missing all the Tax Codes, despite all other fields (item, description, quantity, custom pricing, et al) carrying over correctly.

Like i said it sounds like a core NetSuite issue. File a case. Things like this need piled on. If enough people report this they take it seriously.

Case filed: I'll see what they say. Last time I tried to file a case about this it ended up with "behavior is expected"; won't let that happen again.