These are the email replys I got from Bailey Caravans and ALKO when I first enquired about using a winch.
Dear Michael Thank you for your email regarding your Bailey Ranger 550/6.I can confirm that the only recommended point for any winch or pulley system is on the axle.Damage to the caravan can occur if any other point is used.
I trust this is of assistance
Kelly Watts Bailey Helpline
This is the reply from Bailey Caravans
Dear Mr Cann,I must apologise for the delay in replying to your email request.
As per our information sheet No 6, the axle is the strongest part of the chassis that should be used when “winching” a caravan the only other possible location would be something attached to the ball coupling on the similar line of a “Power Wheel Mover”. We would not advise you to use the chassis members for attachment points by the straps.
And this one from ALKO