I guess a few things to be aware of:
1) You really should make your node dialable or this isn't going to work
2) Your upload speed is a factor so that's something to consider too
3) It currently takes much longer to advertise to the public DHT "I have this data" then it does to find the advertisement. If you add data to your node you might need to give it some time to be advertised in the network.

All the above being said, it's a little tricky to diagnose since again if your peer happens to disconnect from the gateway it's game over. Once you've fixed your networking setup it'll be easier to get real data about what's happening