It's come to my attention that some of our worldwide slave nameservers are not updating when changes are made to the DNS on our master nameserver, 'ampr.org' (44.0.0.1).
It will take me a while to contact the operators of those nameservers to ensure that their configurations are correct for them to get the latest changes as they occur.
In the meantime, there may be differences in the answers you get regarding new entries in the DNS depending on which nameserver your query is actually made to.
The way to tell if a particular nameserver is current is to examine the serial number in the ampr.org SOA record as retrieved from it and compare that with the SOA from ampr.org (44.0.0.1). I use the 'dig' tool for this purpose; there are other tools as well. - Brian