hey feefee, in my experience, it's worth paying for the PO fee to check your passport and i think it's about £6
they give you a ref no and a number you can use to check progress on your application
like others have said, you've plenty of time - the papers mention there's a backlog of apps into mid Aug due to the strikes, but a renewal only take 2 weeks usually so you're looking at early Sept to get your new ones back by my reckoning
anyway, be sure to raise your glass please for our youngest - it's her bday on 5 Oct