A possible application of DAFNE after the end of the Siddharta RUN is using the positron ring as Linac pulse stretcher to produce a high duty=factor beam. The PADME experiment, dedicated to the search for the dark photon (A’), is going to use the BTF beam with 200 ns pulse length and 49 Hz repetition rate, corresponding to a duty-factor of 10e-5. The low duty-factor is the major limitation for the PADME experiment at BTF. By injecting the beam in the DAFNE positron ring and by extracting it with a slow resonant extraction on the m/3 resonance, a duty factor (10e-2 = 0.2/20 ms) nearly a factor 1000 larger can be achieved. This extracted beam would be extremely interesting for PADME. In this talk the modifications required for the ring and the transfer line and a lattice satisfying the conditions for the resonant extraction will be presented. A preliminary estimate of the characteristics of the extracted beam extraction and a description of the work still needed to optimize the parameters will be given.