I think that 1975 taught the GB that setting a hard date was a very bad idea. Even in the runup to 1975, they often tried to hedge their bets by claiming that they weren't making any such prediction. I guess that they understood that they would need to point to those claims if things did not happen as expected.
I think that they switched to pointing at 'signs.' Like 1986, when the UN proclaimed that year to be the year of peace and security. For the WTS, that was a clear reference to Paul's letter stating that the cry of peace and security would be the catalyst for the end. But, like any other signs that they pointed to, nothing happened. If there were more natural disasters than usual, they would remark about it. If there was political upheaval, they would point it out.
Sign after sign after sign that we were at the very end... and nothing would happen. I don't even recall noticing the 1995 change, but by then the doubts had accumulated enough that I was beginning to fade even though I didn't want it or even realize it.