Ryanair are supposedly considering Airbus as well though long term committed Boeing customers may find it worthwhile to stick with Boeing and drive very hard on price whilst being number one in the queue for the new narrow body MAX replacement when it arrives. A clean sheet design would probably outperform the A320NEO so Airbus might get into an arms race with Boeing to build an even better A320 replacement, something both companies have tried to avoid.
Of course it could just be a bargaining position. Airbus didn't bother talking to British Airways for years as they felt they were wasting their time and were simply being used to help BA get a better price from Boeing. When BA first bought Airbus aircraft they had to go to Toulouse and convince the sales department that they were serious.