One thing is for certain - you definitely don't know
A Brit doesn't need to pay for a settlement visa for their partner?
Common sense tells you that if you start prioritising applications others will NOT be prioritised and a queue forms as these will be fast tracked in 24 hrs, unless you can post me in a link showing they have taken on extra staff just to deal with these visa apps.
Less that 24 hrs to process this visa? It's up to 15 working days to process 90% of visit visas, and 12 weeks for up to 95% of settlement visas. Why 12wks ??
You say they do more background checks for a settlement visa. Like what ?? And why don't they do these checks for everyone else ?