OLCI will be free for promo fares, but only those which are free, £1 or £5. So does that mean the more common £10 and £15 fares will incur the charge?
Also, the press release on the Ryanair website doesn't make it completely clear that this includes people who only have hand luggage. It may yet not (we'll find out next week). What if you have no luggage at all? Maybe that will be free?