"...have to wait 5 weeks for any universal credit."
Really? I think someone isn't quite telling the truth here.
Once you've gone through the process of verifying your identity at the Jobcentre you can get an immediate advance of up to your total monthly payment.
You then need to pay this back over anything from 6 to 24 months (you get to choose).
Here is an example. You apply for UC on 3rd July, the assessment period ends on 2nd August so you get your UC on 9th August. Your expected payment is £1,000.
You go along to the Jobcentre and provide all the stuff that they need, or do it online for housing costs etc.
This is quite often done within one week or perhaps two. You can then apply for an advance of up to your expected payment. You will receive this money within two or three days.
So, in this example, that is likely to be in mid July when you receive £1,000.
If you choose to repay over 24 months then, in this example £1,000/24 = £41.66 will be deducted from each payment and you will then receive £958.34 per month.
You will receive the first payment of £958.34 on the 9th August in this example.
So, it is entirely possible to get almost twice the monthly amount of UC within five weeks if you take an advance as soon as possible and then pay it back over 24 months.