Solihull PEO - can I pay after getting ILR

[Kishorbm]

I've read on some posts that at Solihull PEO you can actually pay the fees after getting you ILR rather than at first as at Croydon PEO? what happens if ILR is rejected, do you have to pay anything? Why is there a difference?
Thanks

[geriatrix]

In Solihull, it appears, one is asked to pay the fees when the caseworker has assessed your application ... and confirms that settlement will be granted (so, not "payment after getting ILR" but "payment after being told that ILR will be granted").

However, in Croydon for example, a caseworker gets to see your application only after you have made the payment.

Why is does the process vary (in different PEOs)? Only UKBA can answer that.