Police can confirm a 49-year-old woman from Redhill, Surrey, and a 72-year-old man, originally from the Derby area, were due to answer bail on Sunday, September 26, 2010.
The suspects did not report to Newport Police Station on the Isle of Wight as expected. They remain on police bail pending further enquiries.
The man and woman were arrested on suspicion of being involved in an act of outraging public decency on Sunday, August 8, 2010 when members of the public reported concerns about two people who appeared to be involved in a sexual act on the beach.
Investigating officers would still like to speak with members of the public who had been on Shanklin beach on the afternoon of Sunday, August 8. Several witnesses left the scene without passing on their contact details to the police.
Anyone with information is asked to phone Shanklin Police Station on 101. From outside Hampshire and the Isle of Wight, call the police on 0845 045 45 45. Mini-Com users can call the police on 01962 875000. Information can be given anonymously by calling the Crimestoppers charity on 0800 555 111.