Lee Elder is the expert on this, but if you ask the random JW, they will say they do not take hwole blood or bloods "main components" like red blood cells, plasma, white cells, and whatever the 4th is. Whole blood can leave the body and come back as long as it is part of a "current therapy" which has various definitions.
The most notable change that is really under the radar, is that rarely are people disfellowshipped for this anymore. Basically they were told to lay off people. All you have to do is be under duress when you took the blood, and you are free and clear. Even if you aren't, it would take quite a bit for them to make a major issue of it. Why? Good question. I am not certain.
My theory is that if it hit the news, it would appear JW's are forbidding their member certain types of medical treatment, which would continue to flame the fires of reconsidering them a legitimate religion in most civilized countries.
It is the golden nail in their coffin......and they are stuck with it. Even if they reversed it, the deaths of many memebers and poorly written and conceived previous articles martyring others, would bite them. Their acceptance of fractions in their mind did away with 99% of their problem.
I call this the life insurance doctrine. Its something you never think about until you need to. It seems so far off, and not a big deal, until its your family. Until its you. Until it becomes real that it is quite literally life and death. Its easy for people to say "well they are alive in Jehovahs memory as faithful servants", until you are looking at your child figting every natural instinct you have. And in reasoning with others from that place, you can come off as fanatical, because its so emotional. i have found this out the hard way.
Its a difficult subject to breach, even though it is EASY to disprove.