I'm sorry but I can't help with the GPS question - I do however have an entry in for the event and know it well. It was my first ever audax in 2010 and I have done it multiple times since then. The route itself is fairly straightforward and should be relatively easy to follow from the routesheet if you have GPS problems and there is no-one else around to ride with. I will be on a beaten up Genesis Croix de Fer and will happily provide guided tours
The only things that I can think of to add to what others have said is that there will almost certainly be tea/coffee and biscuits available at the start and there will be a good spread at the finish. Although Burrough Hill is the most prominent climb it is just a long steady drag - I have always found the choppy countryside towards the end after Cranoe more of a challenge - probably because I am more tired by then. Please note that final info will probably not be sent out until the week before the event after route checks have been completed.
@13 rider I was talking to the organiser on Sunday and he reckoned that they are almost full so don't delay in getting your entry in if you want a place!
This was from a mate doing a preliminary route check a couple of weeks ago:
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