25th anniversary of the launch of itv generic idents

This is the problem I've always had, I can full understand why the money has always been place on the 4th September, but over the years people keep making points the actually date was 1st September, with the Launch of LWT at 17.15.

I cant remember who said it but TT made the change over around that time on 1st September, No clips of around this time and nothing appears in the newspapers.

It would be nice to clear this one up once and fall all.

An article on Transdiffusion claims that it was launched on a Saturday (most likely the 2nd of September), at least on YTV:
http://www.transdiffusion.org/2001/09/01/package

There are a few post saying Friday: http://www.tvforum.co.uk/tvhome/date-pres-38322/page-8

Considering that was a nine year old who saw the ident that morning, it may be that his parents simply had BBC or Channel 4 on the previous evening, at least from it's launch until his bedtime. He could've easily missed it on the Friday.

Were they even launched in all regions at the same time. Just as some regions didn't need to think twice about dropping them I suspect some didn't rush them to air either.

YTV definitely launched those idents on Friday evening, 1st Sept. I think all regions that adopted the ITV generic idents launched them in the same night (with Thames following on the Monday morning obviously).

The Chart Show became the ITV Chart Show from Sunday 2nd September.

<blockquote class="twitter-tweet" lang="en"><p>It was a long time ago but if I remember the ITV corporate look came to LWT on 1st September 1989 and to Thames on the 4th.</p>&mdash; Adam Beckwith (@AdamNostalgia) <a href="https://twitter.com/AdamNostalgia/status/507577202939289600">September 4, 2014</a></blockquote>
<script async src="//platform.twitter.com/widgets.js" charset="utf-8"></script>

It was a long time ago but if I remember the ITV corporate look came to LWT on 1st September 1989 and to Thames on the 4th.

— Adam Beckwith (@AdamNostalgia) September 4, 2014

You can't have a Friday 1st and Sunday 2nd.

Here is ITV chat show from Saturday 2nd September 1989:

Although the individual stations were still independent and perhaps theoretically could've chosen to delay launching the generic idents, I feel a 'Big Bang' approach of all participating stations changing together was the desired approach, especially considering the rebranding of shows like the Chart Show, Childrens ITV etc. Obviously, I would't bet on my life that they all changed on the same day, but that would be my educated guess. Similar to the scenario with the generic idents of 1999.

Friday 1st September seems the likely date then, with the first ITV Chart Show the following day; Saturday 2nd.

@tvlive @AdamNostalgia HTV also launched their versions of the 1989 ITV Generic look on September 1st as well.

— Allen Jeremy (@allenjeremy) September 4, 2014