Order=ASC not working?

I’m having trouble getting the ‘order’ argument working.

i.e. this link:
http://pinetreecatering.com/LM/?json=get_recent_posts&post_type=locations&custom_fields=lm-date,time,location,map,coordinates&orderby=meta_value&meta_key=lmdate&order=ASC&callback=listPosts

…does not retrieve any recent posts (in 2015), but:

http://pinetreecatering.com/LM/?json=get_recent_posts&post_type=locations&custom_fields=lm-date,time,location,map,coordinates&orderby=meta_value&meta_key=lmdate&callback=listPosts
does retrieve them.

Any ideas?

https://wordpress.org/plugins/json-api/