Be careful with a GIA and ACC funds

This may be obvious to many but it wasn't to me when I started. I'd filled my ISA allowance so started buying funds within my GIA. The issue is that to calculate the tax owed on the reinvested dividends is complicated when if I'd bought DIST funds to begin with it wouldn't be.

I'm handy with a spreadsheet so I'll calculate my ERI in due course but going forward my regular investments will be in DIST funds only (with automatic reinvestment switched off). Plan is to sell 20K of my ACC funds in April and move the cash into my ISA where it doesn't matter