No need to apologize, the goal of this GREAT STEP FORUM, form the first time it is initiated, is to support the researchers from around the world by ESA, and also the members of this STEP FORUM, try up their best to help each other… this is my understanding 
The idea of the PSI, is to find a coherent point scatterer for long term, during the processing you’ll find that some pairs should be removed because of many related problems such as jump phases, or many others, that’s why one reason is to have many images as much as we can,
Please take a look at this,
Persistent Scatterer Interferometry: A review
In your case if there are no more images than 11, never mind, you could try, by selecting one as master and the other 10 as slaves, the suitable master could be selected by applying InSAR overview, to check up which one of the 11 is the best master.
Also now I found a very good summary, it is done by our colleague @ABraun you could go through it