I did a RB once when I was down in london..only had 2 bids placed, one gave almost no info, the other one had her location as listed as BRIGHTON on her profile...when I messaged to confirm I was talking about someone coming to me in LONDON, she said yes she'll be in the city, so I accepted her and rejected the other.
The morning of the meet, she messaged to say she was ill so couldn't make it now, the one I rejected didnt get back to me, and I couldn't get anyone else on such short notice. Complete waste of time!
As for sundays..virtually none that ive ever contacted have been available on a sunday!