Ron, you may be the victim of emotional blackmail here. I know some lowlifes will spin these tales of imminent dumping to ensure rescuers say "Yes" to taking their cast-offs in, so jumping the waiting list.
The next step, generally, seems to be that you'll find them thrown over your garden wall or abandoned in a box on your doorstep.
Can't say I've seen any "Neuter your pet" campaigns this year from the RSPCA, just more begging for cash ads. I also wonder why it is so difficult to get hold of C4 vouchers for neutering strays, surely it's better value in the long term for the RSPCA to sponsor more neuter operations than allow this crazy situation to get worse? Prevention, not cure?