No thats not true. I ran my masternode for a few weeks and the rewards were inconsistent. Yes I was online when the payments increased to 13 coins each and other days there were no rewards. I've run masternodes for many different coins. And your members in the slack channel are saying the same about the inconsistent rewards. Good project, but that was a deterrent for me.
If they are up and running they should get rewards. However, the selection of masternodes is randomized, therefore you may have three days without rewards or three rewards per day. In the long run the average is daily (considering 400 block per day and 400 masternodes running). Hope it clarifies. I you don't get rewards after three days, check out the masternode shows as running, if not, double check all the parameters as it's easy to mess up, especially if you have more than one. If you still have questions, ask in the slack #masternode channel, everyone there is willing to help.