HB - 8 week arrears from outset

Hi everyone,

I'm very new to been a landlord so I'm learning the hardway.

I've just had my first HB tenant that ended up absconding owing £1000.

She started out badly, I allow them a week or so to get their claim transfered and back dated.
It got to week 5 and still no money, she the finally paid a week and said that it took ages to sort her claim and they hadn't back dated her money.
When I spoke to housing they told me it did take a long time, but all the money had been back dated and she must have spent it.

So I was talking to HB about how to protect myself from this and I was told that I can write the contract so I ask for 88 weeks rent to start off, thus they are automatically in 8 weeks arrears.
Thus from the outset I can get the HB paid to me directly, which would make me happier.

So my question is, does anyone know how to word this in the contract as I don't have the foggiest.

Regards
Neil