I think you will find it has to be done in the one day unless you can prove that some Tech issue occurred which demanded an overnight stop.
Nope - I believe the key figure here is 24 hours. So long as no more than 24 hours have lapsed since you started up at the original departure aerodrome, and within that time you have flown 300 NM and stopped at two different aerodromes, you're fine.
Technically you could leave somewhere like Southend for example at 1400Z, fly up to Welshpool and stop there for the night. Next morning, fly to Lydd, and that's your CPL qualifier done. Have a sandwich and fly the short leg back to Southend.
Done and dusted.
