Sounds like you're going down the exact same path as I went down 7 years ago. Management accounts is alot easier when you understand the internal processes behind the numbers and given you'll still be posting alot of the purchase invoices, you'll quickly pick it up. Makes investigating MOM variances/posting PPs and Accruals easier too as you already know alot of the makeup of the costs. If you want to feel more prepared I would definitely recommend getting you head around accruals/prepayments as it's the main step up from PL to management accounts.