I know my maths GCSE was a long time ago but ...

[Beachsidesunset]

Can any clever people make this make sense? Do I owe them or do they owe me? I pay on the 1st of every month (last payment made on 01/05) and I informed them that we're moving out of the property on the 10th June.

You are owed by them. They calculate your council tax to the last day you will be liable.

If the £314 is your annual charge with the £208 being the amount you pay less a discount (looks like 25%) then you need to divide £208.80 by 365 and multiply by the number of days you live at that address. If you have already paid them more than that amount then they owe you.

You are in credit.

I've worked it out! The £150 rebate thing has been added on. Now, will they refund it to me, or will the next owners get it ...

A very good question, OP. You need to get on to your local authority.

They shouldn't produce a bill in advance of you moving out just in case any issues arise and you don't leave the property for whatever reason. I used to work in council tax, we would advise direct debits to be left in place and if you are in the same council tax area it carries over to your new property. If you move out of area or are no longer liable for council tax any monies owed or refunds due are then taken from your account or refunded into your account, easiest way to do it rather than having a cheque sent out that you then have to pay into a bank. This will be on the final bill so you can see exactly what the amount is and when it will be taken or refunded.

If you make your payment on 1st June as usual then you should be in credit. You are billed for 12 months but the standard is to pay over 10 months. This means each month you pay covers that month plus money toward the 2 months that no payment is collected ie February and March.

From the above it isn't a full account so I can't quite make it out as there isn't a year's charge showing as there are no dates showing from and to.

Thank you, OntheBench. The online system says 'account now closed' and 'no further payments required'.