Assigning collar numbers

[bearsnva]

Is there any difference at all in the way the astro (220 or 320) will track a collar if the collar has been held next to the astro to be assigned a number or whether the number has been manually assigned? Will the Astro track the collar assigned by it before it will track another collar with the same number, say a collar from an entirely different group of hunters? Some of our group says if you manually assign a number to a collar you don't know if you are tracking your collar or another collar with the same number? Hope this question makes sense. Thanks