Originally Posted by
fjfv19
If the tail number is not available and I tell you it is necessary for distinguishing between the two, one would deduce that you can't distinguish. @:-)
In addition, I actually did try to help by posting the fleet tracking website which will be useful for this and any other future aircraft amenity questions. I was trying to be helpful.
You stated as follows:
Get the aircraft / registration number, then refer to here:
https://sites.google.com/site/united...fleet-tracking
The one thing I will say is that it is very difficult to know that far in advance exactly which 739 you'll be getting. Maybe others have a better way of figuring it out.
Nowhere in the post did you state "it is necessary for distinguishing between the two". You stated it is "very difficult"; you did not state it was impossible or "necessary".
But, we'll leave it that for purposes of understanding which version is on a given route more than a few days prior to departure, you don't know.