FWIW, BuddyBeacon in ViewRanger can store positions if it can't upload (ie no signal) and then send them when back online
I used ViewRanger's BuddyBeacon when out cycling in case I end up in a hedge. IIRC, the app is free and you pay if you want extra (detailed) maps. Runs on Apple, Android and some other phones.
T-shirt - means less suncream to put on!
Myprotein does unflavoured electrolyte powder - never tried it myself though
Having run the half in 2012, I get the e-mail newsletters. The one I got yesterday said places were being limited this year with 16,000 for the full marathon.
The e-mail from the end of January's (2014) claimed 3,300 people had signed up already.
Rewind to 2013, I got an e-mail at the start of September saying about 14,000 people had registered.
Best thing might be to get on the official mailing list as the e-mails say when they are getting close to the limit.
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